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

   1 #include "ffmpeg_capture.h"
   2
   3 #include <assert.h>
   4 #include <pthread.h>
   5 #include <stdint.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <unistd.h>
  10
  11 extern "C" {
  12 #include <libavcodec/avcodec.h>
  13 #include <libavformat/avformat.h>
  14 #include <libavutil/avutil.h>
  15 #include <libavutil/error.h>
  16 #include <libavutil/frame.h>
  17 #include <libavutil/imgutils.h>
  18 #include <libavutil/mem.h>
  19 #include <libavutil/pixfmt.h>
  20 #include <libswscale/swscale.h>
  21 }
  22
  23 #include <chrono>
  24 #include <cstdint>
  25 #include <utility>
  26 #include <vector>
  27
  28 #include "bmusb/bmusb.h"
  29 #include "ffmpeg_raii.h"
  30 #include "flags.h"
  31 #include "image_input.h"
  32
  33 #define FRAME_SIZE (8 << 20)  // 8 MB.
  34
  35 using namespace std;
  36 using namespace std::chrono;
  37 using namespace bmusb;
  38
  39 FFmpegCapture::FFmpegCapture(const string &filename, unsigned width, unsigned height)
  40         : filename(filename), width(width), height(height)
  41 {
  42         // Not really used for anything.
  43         description = "Video: " + filename;
  44 }
  45
  46 FFmpegCapture::~FFmpegCapture()
  47 {
  48         if (has_dequeue_callbacks) {
  49                 dequeue_cleanup_callback();
  50         }
  51 }
  52
  53 void FFmpegCapture::configure_card()
  54 {
  55         if (video_frame_allocator == nullptr) {
  56                 owned_video_frame_allocator.reset(new MallocFrameAllocator(FRAME_SIZE, NUM_QUEUED_VIDEO_FRAMES));
  57                 set_video_frame_allocator(owned_video_frame_allocator.get());
  58         }
  59         if (audio_frame_allocator == nullptr) {
  60                 owned_audio_frame_allocator.reset(new MallocFrameAllocator(65536, NUM_QUEUED_AUDIO_FRAMES));
  61                 set_audio_frame_allocator(owned_audio_frame_allocator.get());
  62         }
  63 }
  64
  65 void FFmpegCapture::start_bm_capture()
  66 {
  67         if (running) {
  68                 return;
  69         }
  70         running = true;
  71         producer_thread_should_quit = false;
  72         producer_thread = thread(&FFmpegCapture::producer_thread_func, this);
  73 }
  74
  75 void FFmpegCapture::stop_dequeue_thread()
  76 {
  77         if (!running) {
  78                 return;
  79         }
  80         running = false;
  81         producer_thread_should_quit = true;
  82         producer_thread.join();
  83 }
  84
  85 std::map<uint32_t, VideoMode> FFmpegCapture::get_available_video_modes() const
  86 {
  87         // Note: This will never really be shown in the UI.
  88         VideoMode mode;
  89
  90         char buf[256];
  91         snprintf(buf, sizeof(buf), "%ux%u", width, height);
  92         mode.name = buf;
  93
  94         mode.autodetect = false;
  95         mode.width = width;
  96         mode.height = height;
  97         mode.frame_rate_num = 60;
  98         mode.frame_rate_den = 1;
  99         mode.interlaced = false;
 100
 101         return {{ 0, mode }};
 102 }
 103
 104 void FFmpegCapture::producer_thread_func()
 105 {
 106         char thread_name[16];
 107         snprintf(thread_name, sizeof(thread_name), "FFmpeg_C_%d", card_index);
 108         pthread_setname_np(pthread_self(), thread_name);
 109
 110         while (!producer_thread_should_quit) {
 111                 string pathname = search_for_file(filename);
 112                 if (filename.empty()) {
 113                         fprintf(stderr, "%s not found, sleeping one second and trying again...\n", filename.c_str());
 114                         sleep(1);
 115                         continue;
 116                 }
 117                 if (!play_video(pathname)) {
 118                         // Error.
 119                         fprintf(stderr, "Error when playing %s, sleeping one second and trying again...\n", pathname.c_str());
 120                         sleep(1);
 121                         continue;
 122                 }
 123
 124                 // Probably just EOF, will exit the loop above on next test.
 125         }
 126
 127         if (has_dequeue_callbacks) {
 128                 dequeue_cleanup_callback();
 129                 has_dequeue_callbacks = false;
 130         }
 131 }
 132
 133 bool FFmpegCapture::play_video(const string &pathname)
 134 {
 135         auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, nullptr);
 136         if (format_ctx == nullptr) {
 137                 fprintf(stderr, "%s: Error opening file\n", pathname.c_str());
 138                 return false;
 139         }
 140
 141         if (avformat_find_stream_info(format_ctx.get(), nullptr) < 0) {
 142                 fprintf(stderr, "%s: Error finding stream info\n", pathname.c_str());
 143                 return false;
 144         }
 145
 146         int video_stream_index = -1, audio_stream_index = -1;
 147         AVRational video_timebase{ 1, 1 };
 148         for (unsigned i = 0; i < format_ctx->nb_streams; ++i) {
 149                 if (format_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
 150                     video_stream_index == -1) {
 151                         video_stream_index = i;
 152                         video_timebase = format_ctx->streams[i]->time_base;
 153                 }
 154                 if (format_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&
 155                     audio_stream_index == -1) {
 156                         audio_stream_index = i;
 157                 }
 158         }
 159         if (video_stream_index == -1) {
 160                 fprintf(stderr, "%s: No video stream found\n", pathname.c_str());
 161                 return false;
 162         }
 163
 164         const AVCodecParameters *codecpar = format_ctx->streams[video_stream_index]->codecpar;
 165         AVCodecContextWithDeleter codec_ctx = avcodec_alloc_context3_unique(nullptr);
 166         if (avcodec_parameters_to_context(codec_ctx.get(), codecpar) < 0) {
 167                 fprintf(stderr, "%s: Cannot fill codec parameters\n", pathname.c_str());
 168                 return false;
 169         }
 170         AVCodec *codec = avcodec_find_decoder(codecpar->codec_id);
 171         if (codec == nullptr) {
 172                 fprintf(stderr, "%s: Cannot find decoder\n", pathname.c_str());
 173                 return false;
 174         }
 175         if (avcodec_open2(codec_ctx.get(), codec, nullptr) < 0) {
 176                 fprintf(stderr, "%s: Cannot open decoder\n", pathname.c_str());
 177                 return false;
 178         }
 179         unique_ptr<AVCodecContext, decltype(avcodec_close)*> codec_ctx_cleanup(
 180                 codec_ctx.get(), avcodec_close);
 181
 182         steady_clock::time_point start = steady_clock::now();
 183
 184         unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(nullptr, sws_freeContext);
 185         int sws_last_width = -1, sws_last_height = -1;
 186
 187         // Main loop.
 188         while (!producer_thread_should_quit) {
 189                 // Process any queued commands from other threads.
 190                 vector<QueuedCommand> commands;
 191                 {
 192                         lock_guard<mutex> lock(queue_mu);
 193                         swap(commands, command_queue);
 194                 }
 195                 for (const QueuedCommand &cmd : commands) {
 196                         if (cmd.command == QueuedCommand::REWIND) {
 197                                 if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) {
 198                                         fprintf(stderr, "%s: Rewind failed, stopping play.\n", pathname.c_str());
 199                                 }
 200                                 start = steady_clock::now();
 201                                 continue;
 202                         }
 203                 }
 204
 205                 // Read packets until we have a frame or there are none left.
 206                 int frame_finished = 0;
 207                 AVFrameWithDeleter frame = av_frame_alloc_unique();
 208                 bool eof = false;
 209                 do {
 210                         AVPacket pkt;
 211                         unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
 212                                 &pkt, av_packet_unref);
 213                         av_init_packet(&pkt);
 214                         pkt.data = nullptr;
 215                         pkt.size = 0;
 216                         if (av_read_frame(format_ctx.get(), &pkt) == 0) {
 217                                 if (pkt.stream_index != video_stream_index) {
 218                                         // Ignore audio for now.
 219                                         continue;
 220                                 }
 221                                 if (avcodec_send_packet(codec_ctx.get(), &pkt) < 0) {
 222                                         fprintf(stderr, "%s: Cannot send packet to codec.\n", pathname.c_str());
 223                                         return false;
 224                                 }
 225                         } else {
 226                                 eof = true;  // Or error, but ignore that for the time being.
 227                         }
 228
 229                         int err = avcodec_receive_frame(codec_ctx.get(), frame.get());
 230                         if (err == 0) {
 231                                 frame_finished = true;
 232                                 break;
 233                         } else if (err != AVERROR(EAGAIN)) {
 234                                 fprintf(stderr, "%s: Cannot receive frame from codec.\n", pathname.c_str());
 235                                 return false;
 236                         }
 237                 } while (!eof);
 238
 239                 if (!frame_finished) {
 240                         // EOF. Loop back to the start if we can.
 241                         if (av_seek_frame(format_ctx.get(), /*stream_index=*/-1, /*timestamp=*/0, /*flags=*/0) < 0) {
 242                                 fprintf(stderr, "%s: Rewind failed, not looping.\n", pathname.c_str());
 243                                 return true;
 244                         }
 245                         start = steady_clock::now();
 246                         continue;
 247                 }
 248
 249                 if (sws_ctx == nullptr || sws_last_width != frame->width || sws_last_height != frame->height) {
 250                         sws_ctx.reset(
 251                                 sws_getContext(frame->width, frame->height, (AVPixelFormat)frame->format,
 252                                         width, height, AV_PIX_FMT_RGBA,
 253                                         SWS_BICUBIC, nullptr, nullptr, nullptr));
 254                         sws_last_width = frame->width;
 255                         sws_last_height = frame->height;
 256                 }
 257                 if (sws_ctx == nullptr) {
 258                         fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str());
 259                         return false;
 260                 }
 261
 262                 VideoFormat video_format;
 263                 video_format.width = width;
 264                 video_format.height = height;
 265                 video_format.stride = width * 4;
 266                 video_format.frame_rate_nom = video_timebase.den;
 267                 video_format.frame_rate_den = av_frame_get_pkt_duration(frame.get()) * video_timebase.num;
 268                 video_format.has_signal = true;
 269                 video_format.is_connected = true;
 270
 271                 const duration<double> pts(frame->pts * double(video_timebase.num) / double(video_timebase.den));
 272                 const steady_clock::time_point frame_start = start + duration_cast<steady_clock::duration>(pts);
 273
 274                 FrameAllocator::Frame video_frame = video_frame_allocator->alloc_frame();
 275                 if (video_frame.data != nullptr) {
 276                         uint8_t *pic_data[4] = { video_frame.data, nullptr, nullptr, nullptr };
 277                         int linesizes[4] = { int(video_format.stride), 0, 0, 0 };
 278                         sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
 279                         video_frame.len = video_format.stride * height;
 280                         video_frame.received_timestamp = frame_start;
 281                 }
 282
 283                 FrameAllocator::Frame audio_frame;
 284                 AudioFormat audio_format;
 285                 audio_format.bits_per_sample = 32;
 286                 audio_format.num_channels = 8;
 287
 288                 this_thread::sleep_until(frame_start);
 289                 frame_callback(timecode++,
 290                         video_frame, 0, video_format,
 291                         audio_frame, 0, audio_format);
 292         }
 293         return true;
 294 }