git.sesse.net Git - nageru/blob - nageru/flags.cpp

   1 #include "flags.h"
   2
   3 #include <getopt.h>
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7
   8 #include <utility>
   9
  10 using namespace std;
  11
  12 Flags global_flags;
  13
  14 // Long options that have no corresponding short option.
  15 enum LongOption {
  16         OPTION_HELP = 1000,
  17         OPTION_FULLSCREEN,
  18         OPTION_MAX_NUM_CARDS,
  19         OPTION_MULTICHANNEL,
  20         OPTION_MIDI_MAPPING,
  21         OPTION_DEFAULT_HDMI_INPUT,
  22         OPTION_FAKE_CARDS_AUDIO,
  23         OPTION_V4L_OUTPUT,
  24         OPTION_HTTP_UNCOMPRESSED_VIDEO,
  25         OPTION_HTTP_X264_VIDEO,
  26         OPTION_HTTP_AV1_VIDEO,
  27         OPTION_RECORD_X264_VIDEO,
  28         OPTION_SEPARATE_X264_DISK_ENCODE,
  29         OPTION_X264_PRESET,
  30         OPTION_X264_TUNE,
  31         OPTION_X264_SPEEDCONTROL,
  32         OPTION_X264_SPEEDCONTROL_VERBOSE,
  33         OPTION_X264_BITRATE,
  34         OPTION_X264_CRF,
  35         OPTION_X264_VBV_BUFSIZE,
  36         OPTION_X264_VBV_MAX_BITRATE,
  37         OPTION_X264_PARAM,
  38         OPTION_X264_SEPARATE_DISK_PRESET,
  39         OPTION_X264_SEPARATE_DISK_TUNE,
  40         OPTION_X264_SEPARATE_DISK_BITRATE,
  41         OPTION_X264_SEPARATE_DISK_CRF,
  42         OPTION_X264_SEPARATE_DISK_PARAM,
  43         OPTION_AV1_PRESET,
  44         OPTION_AV1_BITRATE,
  45         OPTION_AV1_FPS,
  46         OPTION_AV1_PARAM,
  47         OPTION_HTTP_MUX,
  48         OPTION_HTTP_COARSE_TIMEBASE,
  49         OPTION_HTTP_AUDIO_CODEC,
  50         OPTION_HTTP_AUDIO_BITRATE,
  51         OPTION_HTTP_PORT,
  52         OPTION_SRT_PORT,
  53         OPTION_NO_SRT,
  54         OPTION_SRT_DESTINATION,
  55         OPTION_SRT_STREAMID,
  56         OPTION_SRT_PASSPHRASE,
  57         OPTION_SRT_YOUTUBE_STREAM_KEY,
  58         OPTION_SRT_LATENCY,
  59         OPTION_NO_TRANSCODE_VIDEO,
  60         OPTION_NO_TRANSCODE_AUDIO,
  61         OPTION_DISABLE_AUDIO,
  62         OPTION_FLAT_AUDIO,
  63         OPTION_GAIN_STAGING,
  64         OPTION_DISABLE_LOCUT,
  65         OPTION_ENABLE_LOCUT,
  66         OPTION_DISABLE_GAIN_STAGING_AUTO,
  67         OPTION_ENABLE_GAIN_STAGING_AUTO,
  68         OPTION_DISABLE_COMPRESSOR,
  69         OPTION_ENABLE_COMPRESSOR,
  70         OPTION_DISABLE_LIMITER,
  71         OPTION_ENABLE_LIMITER,
  72         OPTION_DISABLE_MAKEUP_GAIN_AUTO,
  73         OPTION_ENABLE_MAKEUP_GAIN_AUTO,
  74         OPTION_DISABLE_ALSA_OUTPUT,
  75         OPTION_NO_FLUSH_PBOS,
  76         OPTION_PRINT_VIDEO_LATENCY,
  77         OPTION_MAX_INPUT_QUEUE_FRAMES,
  78         OPTION_AUDIO_QUEUE_LENGTH_MS,
  79         OPTION_OUTPUT_YCBCR_COEFFICIENTS,
  80         OPTION_OUTPUT_BUFFER_FRAMES,
  81         OPTION_OUTPUT_SLOP_FRAMES,
  82         OPTION_OUTPUT_CARD_UNSYNCHRONIZED,
  83         OPTION_TIMECODE_STREAM,
  84         OPTION_TIMECODE_STDOUT,
  85         OPTION_QUICK_CUT_KEYS,
  86         OPTION_10_BIT,
  87         OPTION_10_BIT_INPUT,
  88         OPTION_10_BIT_OUTPUT,
  89         OPTION_INPUT_YCBCR_INTERPRETATION,
  90         OPTION_MJPEG_EXPORT_CARDS,
  91 };
  92
  93 map<unsigned, unsigned> parse_mjpeg_export_cards(char *optarg)
  94 {
  95         map<unsigned, unsigned> ret;
  96         if (optarg[0] == '\0') {
  97                 return ret;
  98         }
  99
 100         unsigned stream_idx = 0;
 101         char *start = optarg;
 102         for ( ;; ) {
 103                 char *end = strchr(start, ',');
 104                 if (end != nullptr) {
 105                         *end = '\0';
 106                 }
 107
 108                 unsigned range_begin, range_end;
 109                 if (sscanf(start, "%u-%u", &range_begin, &range_end) != 2) {
 110                         range_begin = range_end = atoi(start);
 111                 }
 112                 if (range_end < range_begin) {
 113                         fprintf(stderr, "ERROR: Invalid range %u-%u in --mjpeg-export-cards=\n", range_begin, range_end);
 114                         exit(1);
 115                 }
 116                 if (range_end >= unsigned(global_flags.max_num_cards)) {
 117                         // There are situations where we could possibly want to
 118                         // include FFmpeg inputs (CEF inputs are unlikely),
 119                         // but they're not necessarily in 4:2:2 Y'CbCr, so it would
 120                         // require more functionality the the JPEG encoder.
 121                         fprintf(stderr, "ERROR: Asked for (zero-indexed) card %u in --mjpeg-export-cards=, but there are only %u cards\n",
 122                                 range_end, global_flags.max_num_cards);
 123                         exit(1);
 124                 }
 125                 for (unsigned card_idx = range_begin; card_idx <= range_end; ++card_idx) {
 126                         if (ret.count(card_idx)) {
 127                                 fprintf(stderr, "ERROR: Card %u was given twice in --mjpeg-export-cards=\n", card_idx);
 128                                 exit(1);
 129                         }
 130                         ret[card_idx] = stream_idx++;
 131                 }
 132                 if (end == nullptr) {
 133                         break;
 134                 } else {
 135                         start = end + 1;
 136                 }
 137         }
 138         return ret;
 139 }
 140
 141 void usage(Program program)
 142 {
 143         if (program == PROGRAM_KAERU) {
 144                 fprintf(stderr, "Usage: kaeru [OPTION]... SOURCE_URL\n");
 145         } else {
 146                 fprintf(stderr, "Usage: nageru [OPTION]...\n");
 147         }
 148         fprintf(stderr, "\n");
 149         fprintf(stderr, "      --help                      print usage information\n");
 150         if (program == PROGRAM_NAGERU) {
 151                 fprintf(stderr, "      --fullscreen                run in full screen, with no decorations\n");
 152         }
 153         fprintf(stderr, "  -w, --width                     output width in pixels (default 1280)\n");
 154         fprintf(stderr, "  -h, --height                    output height in pixels (default 720)\n");
 155         if (program == PROGRAM_NAGERU) {
 156                 fprintf(stderr, "  -c, --num-cards                 set minimum number of input cards (default 2)\n");
 157                 fprintf(stderr, "      --max-num-cards             set maximum number of input cards (default %d)\n", MAX_VIDEO_CARDS);
 158                 fprintf(stderr, "  -o, --output-card=CARD          also output signal to the given card (default none)\n");
 159                 fprintf(stderr, "  -t, --theme=FILE                choose theme (default theme.lua)\n");
 160                 fprintf(stderr, "  -I, --theme-dir=DIR             search for theme in this directory (can be given multiple times)\n");
 161                 fprintf(stderr, "  -r, --recording-dir=DIR         where to store disk recording\n");
 162                 fprintf(stderr, "  -v, --va-display=SPEC           VA-API device for H.264 encoding\n");
 163                 fprintf(stderr, "                                    ($DISPLAY spec or /dev/dri/render* path)\n");
 164                 fprintf(stderr, "  -m, --map-signal=SIGNAL,CARD    set a default card mapping (can be given multiple times)\n");
 165                 fprintf(stderr, "  -M, --input-mapping=FILE        start with the given audio input mapping (implies --multichannel)\n");
 166                 fprintf(stderr, "      --multichannel              start in multichannel audio mapping mode\n");
 167                 fprintf(stderr, "      --midi-mapping=FILE         start with the given MIDI controller mapping (implies --multichannel)\n");
 168                 fprintf(stderr, "      --default-hdmi-input        default to HDMI over SDI inputs for cards that have both\n");
 169                 fprintf(stderr, "      --fake-cards-audio          make fake (disconnected) cards output a simple tone\n");
 170                 fprintf(stderr, "      --v4l-output=DEVICE         send video (no audio) to V4L2 output/loopback\n");
 171                 fprintf(stderr, "      --http-x264-video           send x264-compressed video to HTTP clients\n");
 172                 fprintf(stderr, "      --record-x264-video         store x264-compressed video to disk (implies --http-x264-video,\n");
 173                 fprintf(stderr, "                                    removes the need for working VA-API encoding)\n");
 174                 fprintf(stderr, "      --separate-x264-disk-encode run a different x264 encoder for disk recording\n");
 175                 fprintf(stderr, "                                    (implies --record-x264-video)\n");
 176         }
 177         fprintf(stderr, "      --x264-preset               x264 quality preset (default " X264_DEFAULT_PRESET ")\n");
 178         fprintf(stderr, "      --x264-tune                 x264 tuning (default " X264_DEFAULT_TUNE ", can be blank)\n");
 179         fprintf(stderr, "      --x264-speedcontrol         try to match x264 preset to available CPU speed\n");
 180         fprintf(stderr, "      --x264-bitrate              x264 bitrate (in kilobit/sec, default %d)\n",
 181                 DEFAULT_X264_OUTPUT_BIT_RATE);
 182         fprintf(stderr, "      --x264-crf=VALUE            quality-based VBR (-12 to 51), incompatible with --x264-bitrate\n");
 183         fprintf(stderr, "      --x264-param=NAME[,VALUE]   set any x264 parameter, for fine tuning\n");
 184         if (program == PROGRAM_NAGERU) {
 185                 fprintf(stderr, "      --x264-separate-disk-preset x264 quality preset (default " X264_DEFAULT_PRESET ")\n");
 186                 fprintf(stderr, "      --x264-separate-disk-tune   x264 tuning (default " X264_DEFAULT_TUNE ", can be blank)\n");
 187                 fprintf(stderr, "      --x264-separate-disk-bitrate  x264 bitrate (in kilobit/sec, default %d)\n",
 188                         DEFAULT_X264_OUTPUT_BIT_RATE);
 189                 fprintf(stderr, "      --x264-separate-disk-crf=VALUE  quality-based VBR (-12 to 51), \n");
 190                 fprintf(stderr, "                                  incompatible with --x264-separate-disk-bitrate\n");
 191                 fprintf(stderr, "      --x264-separate-disk-param=NAME[,VALUE] set any x264 parameter, for fine tuning\n");
 192         }
 193 #ifdef HAVE_AV1
 194         fprintf(stderr, "      --http-av1-video            send AV1-compressed video to HTTP clients and SRT output\n");
 195         fprintf(stderr, "      --av1-preset                SVT-AV1 quality preset (default %d, from -2 to 13)\n",
 196                 DEFAULT_AV1_PRESET);
 197         fprintf(stderr, "      --av1-bitrate               AV1 bitrate (in kilobit/sec, default %d)\n",
 198                 DEFAULT_AV1_OUTPUT_BIT_RATE);
 199         fprintf(stderr, "      --av1-fps=NUM[/DEN]         AV1 encoded frame rate (default %d/%d)\n",
 200                 DEFAULT_AV1_FPS_NUM, DEFAULT_AV1_FPS_DEN);
 201         fprintf(stderr, "      --av1-param=NAME[,VALUE]    set any SVT-AV1 parameter, for fine tuning\n");
 202 #endif
 203         fprintf(stderr, "      --http-mux=NAME             mux to use for HTTP streams (default " DEFAULT_STREAM_MUX_NAME ")\n");
 204         fprintf(stderr, "      --http-audio-codec=NAME     audio codec to use for HTTP streams and SRT output\n");
 205         fprintf(stderr, "                                  (default is to use the same as for the recording)\n");
 206         fprintf(stderr, "      --http-audio-bitrate=KBITS  audio codec bit rate to use for HTTP streams and SRT output\n");
 207         fprintf(stderr, "                                  (default is %d, ignored unless --http-audio-codec is set)\n",
 208                 DEFAULT_AUDIO_OUTPUT_BIT_RATE / 1000);
 209         fprintf(stderr, "      --http-port=PORT            which port to use for the built-in HTTP server\n");
 210         fprintf(stderr, "                                  (default is %d)\n", DEFAULT_HTTPD_PORT);
 211 #ifdef HAVE_SRT
 212         fprintf(stderr, "      --srt-port=PORT             which port to use for receiving SRT streams\n");
 213         fprintf(stderr, "                                  (default is %d)\n", DEFAULT_SRT_PORT);
 214         fprintf(stderr, "      --no-srt                    disable receiving SRT streams\n");
 215 #endif
 216         if (program == PROGRAM_KAERU) {
 217                 fprintf(stderr, "      --no-transcode-video        copy encoded video raw from the source stream\n");
 218                 fprintf(stderr, "                                    (experimental, must be H.264)\n");
 219                 fprintf(stderr, "      --no-transcode-audio        copy encoded audio raw from the source stream\n");
 220                 fprintf(stderr, "                                    (requires --http-audio-codec= to be set)\n");
 221                 fprintf(stderr, "      --disable-audio             do not include any audio in the stream\n");
 222         }
 223         if (program == PROGRAM_NAGERU) {
 224 #ifdef HAVE_SRT
 225                 fprintf(stderr, "      --srt-destination=HOST:PORT  send HTTP video stream also to given destination\n");
 226                 fprintf(stderr, "      --srt-streamid=STREAMID     SRT stream identifying ID\n");
 227                 fprintf(stderr, "      --srt-passphrase=PASSPHRASE  SRT encryption key\n");
 228                 fprintf(stderr, "      --srt-youtube-stream-key=KEY  shortcut for --srt-destination=a.srt.youtube.com:2010\n");
 229                 fprintf(stderr, "                                    --srt-streamid=#!::u=<KEY>,copy=0,encoder=Nageru\n");
 230                 fprintf(stderr, "      --srt-latency=MS            output SRT latency in milliseconds (default is %d)\n", DEFAULT_SRT_OUTPUT_LATENCY_MS);
 231 #endif
 232                 fprintf(stderr, "      --flat-audio                start with most audio processing turned off\n");
 233                 fprintf(stderr, "                                    (can be overridden by e.g. --enable-limiter)\n");
 234                 fprintf(stderr, "      --gain-staging=DB           set initial gain staging to the given value\n");
 235                 fprintf(stderr, "                                    (--disable-gain-staging-auto)\n");
 236                 fprintf(stderr, "      --disable-locut             turn off locut filter (also --enable)\n");
 237                 fprintf(stderr, "      --disable-gain-staging-auto  turn off automatic gain staging (also --enable)\n");
 238                 fprintf(stderr, "      --disable-compressor        turn off regular compressor (also --enable)\n");
 239                 fprintf(stderr, "      --disable-limiter           turn off limiter (also --enable)\n");
 240                 fprintf(stderr, "      --disable-makeup-gain-auto  turn off auto-adjustment of final makeup gain (also --enable)\n");
 241                 fprintf(stderr, "      --disable-alsa-output       disable audio monitoring via ALSA\n");
 242                 fprintf(stderr, "      --print-video-latency       print out measurements of video latency on stdout\n");
 243                 fprintf(stderr, "      --max-input-queue-frames=FRAMES  never keep more than FRAMES frames for each card\n");
 244                 fprintf(stderr, "                                    (default 6, minimum 1)\n");
 245                 fprintf(stderr, "      --audio-queue-length-ms=MS  length of audio resampling queue (default 100.0)\n");
 246                 fprintf(stderr, "      --output-ycbcr-coefficients={rec601,rec709,auto}\n");
 247                 fprintf(stderr, "                                  Y'CbCr coefficient standard of output (default auto)\n");
 248                 fprintf(stderr, "                                    auto is rec601, unless --output-card is used\n");
 249                 fprintf(stderr, "                                    and a Rec. 709 mode (typically HD modes) is in use\n");
 250                 fprintf(stderr, "      --output-buffer-frames=NUM  number of frames in output buffer for --output-card,\n");
 251                 fprintf(stderr, "                                    can be fractional (default 6.0); note also\n");
 252                 fprintf(stderr, "                                    the audio queue can't be much longer than this\n");
 253                 fprintf(stderr, "      --output-slop-frames=NUM    if more less than this number of frames behind for\n");
 254                 fprintf(stderr, "                                    --output-card, try to submit anyway instead of\n");
 255                 fprintf(stderr, "                                    dropping the frame (default 0.5)\n");
 256                 fprintf(stderr, "      --output-card-unsynchronized  if --output-card is in use, do _not_ use it as\n");
 257                 fprintf(stderr, "                                  master clock (may give jittery output and audio breakups)\n");
 258                 fprintf(stderr, "      --timecode-stream           show timestamp and timecode in stream\n");
 259                 fprintf(stderr, "      --timecode-stdout           show timestamp and timecode on standard output\n");
 260                 fprintf(stderr, "      --quick-cut-keys            enable direct cutting by Q, W, E, ... keys\n");
 261                 fprintf(stderr, "      --10-bit                    use 10-bit color depth\n");
 262                 fprintf(stderr, "      --input-ycbcr-interpretation=CARD,{rec601,rec709,auto}[,{limited,full}]\n");
 263                 fprintf(stderr, "                                  Y'CbCr coefficient standard of card CARD (default auto)\n");
 264                 fprintf(stderr, "                                    auto is rec601 for SD, rec709 for HD, always limited\n");
 265                 fprintf(stderr, "                                    limited means standard 0-240/0-235 input range (for 8-bit)\n");
 266                 fprintf(stderr, "      --mjpeg-export-cards=RANGE[,RANGE...]\n");
 267                 fprintf(stderr, "                                  export the given cards in MJPEG format to /multicam.mp4,\n");
 268                 fprintf(stderr, "                                    in the given order (ranges can be either single card indexes\n");
 269                 fprintf(stderr, "                                    or pairs like 1-3 for camera 1,2,3; default is all cards)\n");
 270         }
 271 }
 272
 273 void parse_flags(Program program, int argc, char * const argv[])
 274 {
 275         static const option long_options[] = {
 276                 { "help", no_argument, 0, OPTION_HELP },
 277                 { "fullscreen", no_argument, 0, OPTION_FULLSCREEN },
 278                 { "width", required_argument, 0, 'w' },
 279                 { "height", required_argument, 0, 'h' },
 280                 { "num-cards", required_argument, 0, 'c' },
 281                 { "max-num-cards", required_argument, 0, OPTION_MAX_NUM_CARDS },
 282                 { "output-card", required_argument, 0, 'o' },
 283                 { "theme", required_argument, 0, 't' },
 284                 { "theme-dir", required_argument, 0, 'I' },
 285                 { "recording-dir", required_argument, 0, 'r' },
 286                 { "map-signal", required_argument, 0, 'm' },
 287                 { "input-mapping", required_argument, 0, 'M' },
 288                 { "va-display", required_argument, 0, 'v' },
 289                 { "multichannel", no_argument, 0, OPTION_MULTICHANNEL },
 290                 { "midi-mapping", required_argument, 0, OPTION_MIDI_MAPPING },
 291                 { "default-hdmi-input", no_argument, 0, OPTION_DEFAULT_HDMI_INPUT },
 292                 { "fake-cards-audio", no_argument, 0, OPTION_FAKE_CARDS_AUDIO },
 293                 { "v4l-output", required_argument, 0, OPTION_V4L_OUTPUT },
 294                 { "http-x264-video", no_argument, 0, OPTION_HTTP_X264_VIDEO },
 295                 { "record-x264-video", no_argument, 0, OPTION_RECORD_X264_VIDEO },
 296                 { "separate-x264-disk-encode", no_argument, 0, OPTION_SEPARATE_X264_DISK_ENCODE },
 297                 { "x264-preset", required_argument, 0, OPTION_X264_PRESET },
 298                 { "x264-tune", required_argument, 0, OPTION_X264_TUNE },
 299                 { "x264-speedcontrol", no_argument, 0, OPTION_X264_SPEEDCONTROL },
 300                 { "x264-crf", required_argument, 0, OPTION_X264_CRF },
 301                 { "x264-param", required_argument, 0, OPTION_X264_PARAM },
 302                 { "x264-separate-disk-preset", required_argument, 0, OPTION_X264_SEPARATE_DISK_PRESET },
 303                 { "x264-separate-disk-tune", required_argument, 0, OPTION_X264_SEPARATE_DISK_TUNE },
 304                 { "x264-separate-disk-bitrate", required_argument, 0, OPTION_X264_SEPARATE_DISK_BITRATE },
 305                 { "x264-separate-disk-crf", required_argument, 0, OPTION_X264_SEPARATE_DISK_CRF },
 306                 { "x264-separate-disk-param", required_argument, 0, OPTION_X264_SEPARATE_DISK_PARAM },
 307 #ifdef HAVE_AV1
 308                 { "http-av1-video", no_argument, 0, OPTION_HTTP_AV1_VIDEO },
 309                 { "av1-preset", required_argument, 0, OPTION_AV1_PRESET },
 310                 { "av1-bitrate", required_argument, 0, OPTION_AV1_BITRATE },
 311                 { "av1-fps", required_argument, 0, OPTION_AV1_FPS },
 312                 { "av1-param", required_argument, 0, OPTION_AV1_PARAM },
 313 #endif
 314                 { "http-mux", required_argument, 0, OPTION_HTTP_MUX },
 315                 { "http-audio-codec", required_argument, 0, OPTION_HTTP_AUDIO_CODEC },
 316                 { "http-audio-bitrate", required_argument, 0, OPTION_HTTP_AUDIO_BITRATE },
 317                 { "http-port", required_argument, 0, OPTION_HTTP_PORT },
 318 #ifdef HAVE_SRT
 319                 { "srt-port", required_argument, 0, OPTION_SRT_PORT },
 320 #endif
 321                 { "no-srt", no_argument, 0, OPTION_NO_SRT },  // We silently allow this even without HAVE_SRT.
 322 #ifdef HAVE_SRT
 323                 { "srt-destination", required_argument, 0, OPTION_SRT_DESTINATION },
 324                 { "srt-streamid", required_argument, 0, OPTION_SRT_STREAMID },
 325                 { "srt-passphrase", required_argument, 0, OPTION_SRT_PASSPHRASE },
 326                 { "srt-youtube-stream-key", required_argument, 0, OPTION_SRT_YOUTUBE_STREAM_KEY },
 327                 { "srt-latency", required_argument, 0, OPTION_SRT_LATENCY },
 328 #endif
 329                 { "no-transcode-video", no_argument, 0, OPTION_NO_TRANSCODE_VIDEO },
 330                 { "no-transcode-audio", no_argument, 0, OPTION_NO_TRANSCODE_AUDIO },
 331                 { "disable-audio", no_argument, 0, OPTION_DISABLE_AUDIO },
 332                 { "flat-audio", no_argument, 0, OPTION_FLAT_AUDIO },
 333                 { "gain-staging", required_argument, 0, OPTION_GAIN_STAGING },
 334                 { "disable-locut", no_argument, 0, OPTION_DISABLE_LOCUT },
 335                 { "enable-locut", no_argument, 0, OPTION_ENABLE_LOCUT },
 336                 { "disable-gain-staging-auto", no_argument, 0, OPTION_DISABLE_GAIN_STAGING_AUTO },
 337                 { "enable-gain-staging-auto", no_argument, 0, OPTION_ENABLE_GAIN_STAGING_AUTO },
 338                 { "disable-compressor", no_argument, 0, OPTION_DISABLE_COMPRESSOR },
 339                 { "enable-compressor", no_argument, 0, OPTION_ENABLE_COMPRESSOR },
 340                 { "disable-limiter", no_argument, 0, OPTION_DISABLE_LIMITER },
 341                 { "enable-limiter", no_argument, 0, OPTION_ENABLE_LIMITER },
 342                 { "disable-makeup-gain-auto", no_argument, 0, OPTION_DISABLE_MAKEUP_GAIN_AUTO },
 343                 { "enable-makeup-gain-auto", no_argument, 0, OPTION_ENABLE_MAKEUP_GAIN_AUTO },
 344                 { "disable-alsa-output", no_argument, 0, OPTION_DISABLE_ALSA_OUTPUT },
 345                 { "print-video-latency", no_argument, 0, OPTION_PRINT_VIDEO_LATENCY },
 346                 { "max-input-queue-frames", required_argument, 0, OPTION_MAX_INPUT_QUEUE_FRAMES },
 347                 { "audio-queue-length-ms", required_argument, 0, OPTION_AUDIO_QUEUE_LENGTH_MS },
 348                 { "output-ycbcr-coefficients", required_argument, 0, OPTION_OUTPUT_YCBCR_COEFFICIENTS },
 349                 { "output-buffer-frames", required_argument, 0, OPTION_OUTPUT_BUFFER_FRAMES },
 350                 { "output-slop-frames", required_argument, 0, OPTION_OUTPUT_SLOP_FRAMES },
 351                 { "output-card-unsynchronized", no_argument, 0, OPTION_OUTPUT_CARD_UNSYNCHRONIZED },
 352                 { "timecode-stream", no_argument, 0, OPTION_TIMECODE_STREAM },
 353                 { "timecode-stdout", no_argument, 0, OPTION_TIMECODE_STDOUT },
 354                 { "quick-cut-keys", no_argument, 0, OPTION_QUICK_CUT_KEYS },
 355                 { "10-bit", no_argument, 0, OPTION_10_BIT },
 356                 { "input-ycbcr-interpretation", required_argument, 0, OPTION_INPUT_YCBCR_INTERPRETATION },
 357                 { "mjpeg-export-cards", required_argument, 0, OPTION_MJPEG_EXPORT_CARDS },
 358
 359                 // Do not explicitly signal texture data uploads (will give
 360                 // display corruption, but makes it possible to run with
 361                 // apitrace in real time). For developers only, so undocumented.
 362                 { "no-flush-pbos", no_argument, 0, OPTION_NO_FLUSH_PBOS },
 363
 364                 // Output speedcontrol debugging statistics. For developers only,
 365                 // so undocumented (users can get this information from Prometheus
 366                 // statistics, too).
 367                 { "x264-speedcontrol-verbose", no_argument, 0, OPTION_X264_SPEEDCONTROL_VERBOSE },
 368
 369                 // Deprecated variants.
 370                 { "10-bit-input", no_argument, 0, OPTION_10_BIT_INPUT },
 371                 { "10-bit-output", no_argument, 0, OPTION_10_BIT_OUTPUT },
 372
 373                 { 0, 0, 0, 0 }
 374         };
 375         vector<string> theme_dirs;
 376         string output_ycbcr_coefficients = "auto";
 377         bool card_to_mjpeg_stream_export_set = false;
 378         for ( ;; ) {
 379                 int option_index = 0;
 380                 int c = getopt_long(argc, argv, "c:o:t:I:r:v:m:M:w:h:", long_options, &option_index);
 381
 382                 if (c == -1) {
 383                         break;
 384                 }
 385                 switch (c) {
 386                 case 'w':
 387                         global_flags.width = atoi(optarg);
 388                         break;
 389                 case 'h':
 390                         global_flags.height = atoi(optarg);
 391                         break;
 392                 case 'c':
 393                         global_flags.min_num_cards = atoi(optarg);
 394                         break;
 395                 case OPTION_MAX_NUM_CARDS:
 396                         global_flags.max_num_cards = atoi(optarg);
 397                         break;
 398                 case 'o':
 399                         global_flags.output_card = atoi(optarg);
 400                         break;
 401                 case 't':
 402                         global_flags.theme_filename = optarg;
 403                         break;
 404                 case 'I':
 405                         theme_dirs.push_back(optarg);
 406                         break;
 407                 case 'r':
 408                         global_flags.recording_dir = optarg;
 409                         break;
 410                 case 'm': {
 411                         char *ptr = strchr(optarg, ',');
 412                         if (ptr == nullptr) {
 413                                 fprintf(stderr, "ERROR: Invalid argument '%s' to --map-signal (needs a signal and a card number, separated by comma)\n", optarg);
 414                                 exit(1);
 415                         }
 416                         *ptr = '\0';
 417                         const int signal_num = atoi(optarg);
 418                         const int card_num = atoi(ptr + 1);
 419                         if (global_flags.default_stream_mapping.count(signal_num)) {
 420                                 fprintf(stderr, "ERROR: Signal %d already mapped to card %d\n",
 421                                         signal_num, global_flags.default_stream_mapping[signal_num]);
 422                                 exit(1);
 423                         }
 424                         global_flags.default_stream_mapping[signal_num] = card_num;
 425                         break;
 426                 }
 427                 case 'M':
 428                         global_flags.input_mapping_filename = optarg;
 429                         break;
 430                 case OPTION_MULTICHANNEL:
 431                         global_flags.multichannel_mapping_mode = true;
 432                         break;
 433                 case 'v':
 434                         global_flags.va_display = optarg;
 435                         break;
 436                 case OPTION_MIDI_MAPPING:
 437                         global_flags.midi_mapping_filename = optarg;
 438                         global_flags.multichannel_mapping_mode = true;
 439                         break;
 440                 case OPTION_DEFAULT_HDMI_INPUT:
 441                         global_flags.default_hdmi_input = true;
 442                         break;
 443                 case OPTION_FAKE_CARDS_AUDIO:
 444                         global_flags.fake_cards_audio = true;
 445                         break;
 446                 case OPTION_V4L_OUTPUT:
 447                         global_flags.v4l_output_device = optarg;
 448                         break;
 449                 case OPTION_HTTP_MUX:
 450                         global_flags.stream_mux_name = optarg;
 451                         break;
 452                 case OPTION_HTTP_AUDIO_CODEC:
 453                         global_flags.stream_audio_codec_name = optarg;
 454                         break;
 455                 case OPTION_HTTP_AUDIO_BITRATE:
 456                         global_flags.stream_audio_codec_bitrate = atoi(optarg) * 1000;
 457                         break;
 458                 case OPTION_HTTP_PORT:
 459                         global_flags.http_port = atoi(optarg);
 460                         break;
 461 #ifdef HAVE_SRT
 462                 case OPTION_SRT_PORT:
 463                         global_flags.srt_port = atoi(optarg);
 464                         break;
 465 #endif
 466                 case OPTION_NO_SRT:
 467                         global_flags.srt_port = -1;
 468                         break;
 469 #ifdef HAVE_SRT
 470                 case OPTION_SRT_DESTINATION: {
 471                         const char *ptr = strrchr(optarg, ':');
 472                         if (ptr == nullptr || strlen(optarg) < 3) {
 473                                 fprintf(stderr, "ERROR: --srt-destination must be of the form host:port\n");
 474                                 exit(1);
 475                         }
 476                         global_flags.srt_destination_host = string(optarg, ptr - optarg);
 477                         if (global_flags.srt_destination_host[0] == '[' &&
 478                             global_flags.srt_destination_host.back() == ']') {
 479                                 // Support [IPv6]:port, in a sort of hackish way.
 480                                 global_flags.srt_destination_host = global_flags.srt_destination_host.substr(1, global_flags.srt_destination_host.size() - 2);
 481                         }
 482                         global_flags.srt_destination_port = ptr + 1;
 483                         break;
 484                 }
 485                 case OPTION_SRT_STREAMID:
 486                         global_flags.srt_streamid = optarg;
 487                         break;
 488                 case OPTION_SRT_PASSPHRASE:
 489                         global_flags.srt_passphrase = optarg;
 490                         break;
 491                 case OPTION_SRT_YOUTUBE_STREAM_KEY:
 492                         global_flags.srt_destination_host = "a.srt.youtube.com";
 493                         global_flags.srt_destination_port = "2010";
 494                         global_flags.srt_streamid = string("#!::u=") + optarg + ",copy=0,encoder=Nageru " NAGERU_VERSION;
 495                         break;
 496                 case OPTION_SRT_LATENCY:
 497                         global_flags.srt_output_latency_ms = atoi(optarg);
 498                         break;
 499 #endif
 500                 case OPTION_NO_TRANSCODE_VIDEO:
 501                         global_flags.transcode_video = false;
 502                         break;
 503                 case OPTION_NO_TRANSCODE_AUDIO:
 504                         global_flags.transcode_audio = false;
 505                         break;
 506                 case OPTION_DISABLE_AUDIO:
 507                         global_flags.transcode_audio = false;
 508                         global_flags.enable_audio = false;
 509                         break;
 510                 case OPTION_HTTP_X264_VIDEO:
 511                         global_flags.x264_video_to_http = true;
 512                         break;
 513                 case OPTION_RECORD_X264_VIDEO:
 514                         global_flags.x264_video_to_disk = true;
 515                         break;
 516                 case OPTION_SEPARATE_X264_DISK_ENCODE:
 517                         global_flags.x264_video_to_disk = true;
 518                         global_flags.x264_video_to_http = true;
 519                         global_flags.x264_separate_disk_encode = true;
 520                         break;
 521                 case OPTION_HTTP_AV1_VIDEO:
 522                         global_flags.av1_video_to_http = true;
 523                         break;
 524                 case OPTION_X264_PRESET:
 525                         global_flags.x264_preset = optarg;
 526                         break;
 527                 case OPTION_X264_TUNE:
 528                         global_flags.x264_tune = optarg;
 529                         break;
 530                 case OPTION_X264_SPEEDCONTROL:
 531                         global_flags.x264_speedcontrol = true;
 532                         break;
 533                 case OPTION_X264_SPEEDCONTROL_VERBOSE:
 534                         global_flags.x264_speedcontrol_verbose = true;
 535                         break;
 536                 case OPTION_X264_BITRATE:
 537                         global_flags.x264_bitrate = atoi(optarg);
 538                         break;
 539                 case OPTION_X264_CRF:
 540                         global_flags.x264_crf = atof(optarg);
 541                         break;
 542                 case OPTION_X264_PARAM:
 543                         global_flags.x264_extra_param.push_back(optarg);
 544                         break;
 545                 case OPTION_X264_SEPARATE_DISK_PRESET:
 546                         global_flags.x264_separate_disk_preset = optarg;
 547                         break;
 548                 case OPTION_X264_SEPARATE_DISK_TUNE:
 549                         global_flags.x264_separate_disk_tune = optarg;
 550                         break;
 551                 case OPTION_X264_SEPARATE_DISK_BITRATE:
 552                         global_flags.x264_separate_disk_bitrate = atoi(optarg);
 553                         break;
 554                 case OPTION_X264_SEPARATE_DISK_CRF:
 555                         global_flags.x264_separate_disk_crf = atof(optarg);
 556                         break;
 557                 case OPTION_X264_SEPARATE_DISK_PARAM:
 558                         global_flags.x264_separate_disk_extra_param.push_back(optarg);
 559                         break;
 560                 case OPTION_AV1_PRESET:
 561                         global_flags.av1_preset = atoi(optarg);
 562                         break;
 563                 case OPTION_AV1_BITRATE:
 564                         global_flags.av1_bitrate = atoi(optarg);
 565                         break;
 566                 case OPTION_AV1_FPS: {
 567                         string str = optarg;
 568                         const size_t pos = str.find('/');
 569                         if (pos == string::npos) {
 570                                 global_flags.av1_fps_num = stoi(str);
 571                                 global_flags.av1_fps_den = 1;
 572                         } else {
 573                                 const string num = str.substr(0, pos);
 574                                 const string den = str.substr(pos + 1);
 575                                 global_flags.av1_fps_num = stoi(num);
 576                                 global_flags.av1_fps_den = stoi(den);
 577                         }
 578                         break;
 579                 }
 580                 case OPTION_AV1_PARAM:
 581                         global_flags.av1_extra_param.push_back(optarg);
 582                         break;
 583                 case OPTION_FLAT_AUDIO:
 584                         // If --flat-audio is given, turn off everything that messes with the sound,
 585                         // except the final makeup gain.
 586                         global_flags.locut_enabled = false;
 587                         global_flags.gain_staging_auto = false;
 588                         global_flags.compressor_enabled = false;
 589                         global_flags.limiter_enabled = false;
 590                         break;
 591                 case OPTION_GAIN_STAGING:
 592                         global_flags.initial_gain_staging_db = atof(optarg);
 593                         global_flags.gain_staging_auto = false;
 594                         break;
 595                 case OPTION_DISABLE_LOCUT:
 596                         global_flags.locut_enabled = false;
 597                         break;
 598                 case OPTION_ENABLE_LOCUT:
 599                         global_flags.locut_enabled = true;
 600                         break;
 601                 case OPTION_DISABLE_GAIN_STAGING_AUTO:
 602                         global_flags.gain_staging_auto = false;
 603                         break;
 604                 case OPTION_ENABLE_GAIN_STAGING_AUTO:
 605                         global_flags.gain_staging_auto = true;
 606                         break;
 607                 case OPTION_DISABLE_COMPRESSOR:
 608                         global_flags.compressor_enabled = false;
 609                         break;
 610                 case OPTION_ENABLE_COMPRESSOR:
 611                         global_flags.compressor_enabled = true;
 612                         break;
 613                 case OPTION_DISABLE_LIMITER:
 614                         global_flags.limiter_enabled = false;
 615                         break;
 616                 case OPTION_ENABLE_LIMITER:
 617                         global_flags.limiter_enabled = true;
 618                         break;
 619                 case OPTION_DISABLE_MAKEUP_GAIN_AUTO:
 620                         global_flags.final_makeup_gain_auto = false;
 621                         break;
 622                 case OPTION_ENABLE_MAKEUP_GAIN_AUTO:
 623                         global_flags.final_makeup_gain_auto = true;
 624                         break;
 625                 case OPTION_DISABLE_ALSA_OUTPUT:
 626                         global_flags.enable_alsa_output = false;
 627                         break;
 628                 case OPTION_NO_FLUSH_PBOS:
 629                         global_flags.flush_pbos = false;
 630                         break;
 631                 case OPTION_PRINT_VIDEO_LATENCY:
 632                         global_flags.print_video_latency = true;
 633                         break;
 634                 case OPTION_MAX_INPUT_QUEUE_FRAMES:
 635                         global_flags.max_input_queue_frames = atoi(optarg);
 636                         break;
 637                 case OPTION_AUDIO_QUEUE_LENGTH_MS:
 638                         global_flags.audio_queue_length_ms = atof(optarg);
 639                         break;
 640                 case OPTION_OUTPUT_YCBCR_COEFFICIENTS:
 641                         output_ycbcr_coefficients = optarg;
 642                         break;
 643                 case OPTION_OUTPUT_BUFFER_FRAMES:
 644                         global_flags.output_buffer_frames = atof(optarg);
 645                         break;
 646                 case OPTION_OUTPUT_SLOP_FRAMES:
 647                         global_flags.output_slop_frames = atof(optarg);
 648                         break;
 649                 case OPTION_OUTPUT_CARD_UNSYNCHRONIZED:
 650                         global_flags.output_card_is_master = false;
 651                         break;
 652                 case OPTION_TIMECODE_STREAM:
 653                         global_flags.display_timecode_in_stream = true;
 654                         break;
 655                 case OPTION_TIMECODE_STDOUT:
 656                         global_flags.display_timecode_on_stdout = true;
 657                         break;
 658                 case OPTION_QUICK_CUT_KEYS:
 659                         global_flags.enable_quick_cut_keys = true;
 660                         break;
 661                 case OPTION_10_BIT_INPUT:
 662                         fprintf(stderr, "NOTE: --10-bit-input is a deprecated alias for --10-bit.\n");
 663                         global_flags.bit_depth = 10;
 664                         break;
 665                 case OPTION_10_BIT_OUTPUT:
 666                         fprintf(stderr, "NOTE: --10-bit-output is a deprecated alias for --10-bit.\n");
 667                         global_flags.bit_depth = 10;
 668                         break;
 669                 case OPTION_10_BIT:
 670                         global_flags.bit_depth = 10;
 671                         break;
 672                 case OPTION_INPUT_YCBCR_INTERPRETATION: {
 673                         char *ptr = strchr(optarg, ',');
 674                         if (ptr == nullptr) {
 675                                 fprintf(stderr, "ERROR: Invalid argument '%s' to --input-ycbcr-interpretation (needs a card and an interpretation, separated by comma)\n", optarg);
 676                                 exit(1);
 677                         }
 678                         *ptr = '\0';
 679                         const int card_num = atoi(optarg);
 680                         if (card_num < 0 || card_num >= MAX_VIDEO_CARDS) {
 681                                 fprintf(stderr, "ERROR: Invalid card number %d\n", card_num);
 682                                 exit(1);
 683                         }
 684
 685                         YCbCrInterpretation interpretation;
 686                         char *interpretation_str = ptr + 1;
 687                         ptr = strchr(interpretation_str, ',');
 688                         if (ptr != nullptr) {
 689                                 *ptr = '\0';
 690                                 const char *range = ptr + 1;
 691                                 if (strcmp(range, "full") == 0) {
 692                                         interpretation.full_range = true;
 693                                 } else if (strcmp(range, "limited") == 0) {
 694                                         interpretation.full_range = false;
 695                                 } else {
 696                                         fprintf(stderr, "ERROR: Invalid Y'CbCr range '%s' (must be “full” or “limited”)\n", range);
 697                                         exit(1);
 698                                 }
 699                         }
 700
 701                         if (strcmp(interpretation_str, "rec601") == 0) {
 702                                 interpretation.ycbcr_coefficients_auto = false;
 703                                 interpretation.ycbcr_coefficients = movit::YCBCR_REC_601;
 704                         } else if (strcmp(interpretation_str, "rec709") == 0) {
 705                                 interpretation.ycbcr_coefficients_auto = false;
 706                                 interpretation.ycbcr_coefficients = movit::YCBCR_REC_709;
 707                         } else if (strcmp(interpretation_str, "auto") == 0) {
 708                                 interpretation.ycbcr_coefficients_auto = true;
 709                                 if (interpretation.full_range) {
 710                                         fprintf(stderr, "ERROR: Cannot use “auto” Y'CbCr coefficients with full range\n");
 711                                         exit(1);
 712                                 }
 713                         } else {
 714                                 fprintf(stderr, "ERROR: Invalid Y'CbCr coefficients '%s' (must be “rec601”, “rec709” or “auto”)\n", interpretation_str);
 715                                 exit(1);
 716                         }
 717                         global_flags.ycbcr_interpretation[card_num] = interpretation;
 718                         break;
 719                 }
 720                 case OPTION_FULLSCREEN:
 721                         global_flags.fullscreen = true;
 722                         break;
 723                 case OPTION_MJPEG_EXPORT_CARDS: {
 724                         if (card_to_mjpeg_stream_export_set) {
 725                                 fprintf(stderr, "ERROR: --mjpeg-export-cards given twice\n");
 726                                 exit(1);
 727                         }
 728                         global_flags.card_to_mjpeg_stream_export = parse_mjpeg_export_cards(optarg);
 729                         card_to_mjpeg_stream_export_set = true;
 730                         break;
 731                 }
 732                 case OPTION_HELP:
 733                         usage(program);
 734                         exit(0);
 735                 default:
 736                         fprintf(stderr, "Unknown option '%s'\n", argv[option_index]);
 737                         fprintf(stderr, "\n");
 738                         usage(program);
 739                         exit(1);
 740                 }
 741         }
 742
 743         if (global_flags.x264_video_to_http +
 744             global_flags.av1_video_to_http > 1) {
 745                 fprintf(stderr, "ERROR: --http-{x264,av1}-video are mutually incompatible\n");
 746                 exit(1);
 747         }
 748         if (global_flags.bit_depth == 10) {
 749                 global_flags.x264_video_to_disk = true;  // No 10-bit Quick Sync support.
 750                 if (!global_flags.av1_video_to_http) {
 751                         global_flags.x264_video_to_http = true;
 752                 }
 753         }
 754         if (global_flags.x264_video_to_disk && !global_flags.av1_video_to_http) {
 755                 global_flags.x264_video_to_http = true;  // Quick Sync to HTTP but x264 to disk doesn't make sense.
 756         }
 757         if (global_flags.min_num_cards <= 0) {
 758                 fprintf(stderr, "ERROR: --num-cards must be at least 1\n");
 759                 exit(1);
 760         }
 761         if (global_flags.max_num_cards <= 0) {
 762                 fprintf(stderr, "ERROR: --max-num-cards must be at least 1\n");
 763                 exit(1);
 764         }
 765         if (global_flags.max_num_cards < global_flags.min_num_cards) {
 766                 fprintf(stderr, "ERROR: --max-num-cards can not be lower than --num-cards\n");
 767                 exit(1);
 768         }
 769         if (global_flags.output_card < -1 ||
 770             global_flags.output_card >= global_flags.max_num_cards) {
 771                 fprintf(stderr, "ERROR: --output-card points to a nonexistant card\n");
 772                 exit(1);
 773         }
 774         if (global_flags.enable_audio && !global_flags.transcode_audio && global_flags.stream_audio_codec_name.empty()) {
 775                 fprintf(stderr, "ERROR: If not transcoding audio, you must specify ahead-of-time what audio codec is in use\n");
 776                 fprintf(stderr, "       (using --http-audio-codec).\n");
 777                 exit(1);
 778         }
 779         if (global_flags.x264_speedcontrol) {
 780                 if (!global_flags.x264_preset.empty() && global_flags.x264_preset != "faster") {
 781                         fprintf(stderr, "WARNING: --x264-preset is overridden by --x264-speedcontrol (implicitly uses \"faster\" as base preset)\n");
 782                 }
 783                 global_flags.x264_preset = "faster";
 784         } else if (global_flags.x264_preset.empty()) {
 785                 global_flags.x264_preset = X264_DEFAULT_PRESET;
 786         }
 787         if (global_flags.x264_separate_disk_preset.empty()) {
 788                 global_flags.x264_separate_disk_preset = X264_DEFAULT_PRESET;
 789         }
 790         if (!theme_dirs.empty()) {
 791                 global_flags.theme_dirs = theme_dirs;
 792         }
 793
 794         // In reality, we could probably do with any even value (we subsample
 795         // by two in some places), but it's better to be on the safe side
 796         // wrt. video codecs and such. (I'd set 16 if I could, but 1080 isn't
 797         // divisible by 16.)
 798         if (global_flags.width <= 0 || (global_flags.width % 8) != 0 ||
 799             global_flags.height <= 0 || (global_flags.height % 8) != 0) {
 800                 fprintf(stderr, "ERROR: --width and --height must be positive integers divisible by 8\n");
 801                 exit(1);
 802         }
 803
 804         for (pair<int, int> mapping : global_flags.default_stream_mapping) {
 805                 if (mapping.second >= global_flags.max_num_cards) {
 806                         fprintf(stderr, "ERROR: Signal %d mapped to card %d, which doesn't exist (try adjusting --max-num-cards)\n",
 807                                 mapping.first, mapping.second);
 808                         exit(1);
 809                 }
 810         }
 811
 812         // Rec. 709 would be the sane thing to do, but it seems many players
 813         // just default to BT.601 coefficients no matter what. We _do_ set
 814         // the right flags, so that a player that works properly doesn't have
 815         // to guess, but it's frequently ignored. See discussions
 816         // in e.g. https://trac.ffmpeg.org/ticket/4978; the situation with
 817         // browsers is complicated and depends on things like hardware acceleration
 818         // (https://bugs.chromium.org/p/chromium/issues/detail?id=333619 for
 819         // extensive discussion). VLC generally fixed this as part of 3.0.0
 820         // (see e.g. https://github.com/videolan/vlc/commit/bc71288b2e38c07d6921472824b92eef1aa85f7e
 821         // and https://github.com/videolan/vlc/commit/c3fc2683a9cde1d42674ebf9935dced05733a215),
 822         // but earlier versions were pretty random.
 823         //
 824         // On the other hand, HDMI/SDI output typically requires Rec. 709 for
 825         // HD resolutions (with no way of signaling anything else), which is
 826         // a conflicting demand. In this case, we typically let the HDMI/SDI
 827         // output win if it is active, but the user can override this.
 828         if (output_ycbcr_coefficients == "auto") {
 829                 // Essentially: BT.709 if HDMI/SDI output is on, otherwise BT.601.
 830                 global_flags.ycbcr_rec709_coefficients = false;
 831                 global_flags.ycbcr_auto_coefficients = true;
 832         } else if (output_ycbcr_coefficients == "rec709") {
 833                 global_flags.ycbcr_rec709_coefficients = true;
 834                 global_flags.ycbcr_auto_coefficients = false;
 835         } else if (output_ycbcr_coefficients == "rec601") {
 836                 global_flags.ycbcr_rec709_coefficients = false;
 837                 global_flags.ycbcr_auto_coefficients = false;
 838         } else {
 839                 fprintf(stderr, "ERROR: --output-ycbcr-coefficients must be “rec601”, “rec709” or “auto”\n");
 840                 exit(1);
 841         }
 842
 843         if (global_flags.output_buffer_frames < 0.0f) {
 844                 // Actually, even zero probably won't make sense; there is some internal
 845                 // delay to the card.
 846                 fprintf(stderr, "ERROR: --output-buffer-frames can't be negative.\n");
 847                 exit(1);
 848         }
 849         if (global_flags.output_slop_frames < 0.0f) {
 850                 fprintf(stderr, "ERROR: --output-slop-frames can't be negative.\n");
 851                 exit(1);
 852         }
 853         if (global_flags.max_input_queue_frames < 1) {
 854                 fprintf(stderr, "ERROR: --max-input-queue-frames must be at least 1.\n");
 855                 exit(1);
 856         }
 857         if (global_flags.max_input_queue_frames > 10) {
 858                 fprintf(stderr, "WARNING: --max-input-queue-frames has little effect over 10.\n");
 859         }
 860
 861         if (!isinf(global_flags.x264_crf)) {  // CRF mode is selected.
 862                 if (global_flags.x264_bitrate != -1) {
 863                         fprintf(stderr, "ERROR: --x264-bitrate and --x264-crf are mutually incompatible.\n");
 864                         exit(1);
 865                 }
 866         } else if (global_flags.x264_bitrate == -1) {
 867                 global_flags.x264_bitrate = DEFAULT_X264_OUTPUT_BIT_RATE;
 868         }
 869
 870         if (!isinf(global_flags.x264_separate_disk_crf)) {  // CRF mode is selected.
 871                 if (global_flags.x264_separate_disk_bitrate != -1) {
 872                         fprintf(stderr, "ERROR: --x264-separate-disk-bitrate and --x264-separate-disk-crf are mutually incompatible.\n");
 873                         exit(1);
 874                 }
 875         } else if (global_flags.x264_separate_disk_bitrate == -1) {
 876                 global_flags.x264_separate_disk_bitrate = DEFAULT_X264_OUTPUT_BIT_RATE;
 877         }
 878
 879         if (!card_to_mjpeg_stream_export_set) {
 880                 // Fill in the default mapping (export all cards, in order).
 881                 for (unsigned card_idx = 0; card_idx < unsigned(global_flags.max_num_cards); ++card_idx) {
 882                         global_flags.card_to_mjpeg_stream_export[card_idx] = card_idx;
 883                 }
 884         }
 885
 886         if (global_flags.srt_destination_host == "a.srt.youtube.com" && global_flags.srt_passphrase.empty()) {
 887                 fprintf(stderr, "ERROR: Cannot stream to YouTube without --srt-passphrase (get it from the YouTube streaming console)\n");
 888                 exit(1);
 889         }
 890 }