Support setting x264 bitrate parameters from the command line.

diff --git a/defs.h b/defs.h
index 7654f986bf142bf30c1e476be09c372fd1ade1b3..05a38996747e05e3a4df6dfc05aa1ca31e03dee7 100644 (file)
--- a/defs.h
+++ b/defs.h
@@ -12,6 +12,7 @@
 
 #define AUDIO_OUTPUT_CODEC_NAME "pcm_s32le"
 #define DEFAULT_AUDIO_OUTPUT_BIT_RATE 0
+#define DEFAULT_X264_OUTPUT_BIT_RATE 4500  // 5 Mbit after making room for some audio and TCP overhead.
 
 #define LOCAL_DUMP_PREFIX "record-"
 #define LOCAL_DUMP_SUFFIX ".nut"

diff --git a/flags.cpp b/flags.cpp
index 01f563f5ca8c6ac155ffcc152e0e767af985eabc..c2dd153ed537172538119c1d0049e4e32c1aa32c 100644 (file)
--- a/flags.cpp
+++ b/flags.cpp
@@ -19,6 +19,12 @@ void usage()
        fprintf(stderr, "      --http-x264-video           send x264-compressed video to HTTP clients\n");
        fprintf(stderr, "      --x264-preset               x264 quality preset (default " X264_DEFAULT_PRESET ")\n");
        fprintf(stderr, "      --x264-tune                 x264 tuning (default " X264_DEFAULT_TUNE ", can be blank)\n");
+       fprintf(stderr, "      --x264-bitrate              x264 bitrate (in kilobit/sec, default %d)\n",
+               DEFAULT_X264_OUTPUT_BIT_RATE);
+       fprintf(stderr, "      --x264-vbv-bufsize          x264 VBV size (in kilobits, 0 = one-frame VBV,\n");
+       fprintf(stderr, "                                  default: same as --x264-bitrate, that is, one-second VBV)\n");
+       fprintf(stderr, "      --x264-vbv-max-bitrate      x264 local max bitrate (in kilobit/sec per --vbv-bufsize,\n");
+       fprintf(stderr, "                                  0 = no limit, default: same as --x264-bitrate, i.e., CBR)\n");
        fprintf(stderr, "      --http-mux=NAME             mux to use for HTTP streams (default " DEFAULT_STREAM_MUX_NAME ")\n");
        fprintf(stderr, "      --http-audio-codec=NAME     audio codec to use for HTTP streams\n");
        fprintf(stderr, "                                  (default is to use the same as for the recording)\n");
@@ -44,6 +50,9 @@ void parse_flags(int argc, char * const argv[])
                { "http-x264-video", no_argument, 0, 1008 },
                { "x264-preset", required_argument, 0, 1009 },
                { "x264-tune", required_argument, 0, 1010 },
+               { "x264-bitrate", required_argument, 0, 1011 },
+               { "x264-vbv-bufsize", required_argument, 0, 1012 },
+               { "x264-vbv-max-bitrate", required_argument, 0, 1013 },
                { "http-mux", required_argument, 0, 1004 },
                { "http-coarse-timebase", no_argument, 0, 1005 },
                { "http-audio-codec", required_argument, 0, 1006 },
@@ -93,6 +102,15 @@ void parse_flags(int argc, char * const argv[])
                case 1010:
                        global_flags.x264_tune = optarg;
                        break;
+               case 1011:
+                       global_flags.x264_bitrate = atoi(optarg);
+                       break;
+               case 1012:
+                       global_flags.x264_vbv_buffer_size = atoi(optarg);
+                       break;
+               case 1013:
+                       global_flags.x264_vbv_max_bitrate = atoi(optarg);
+                       break;
                case 1002:
                        global_flags.flat_audio = true;
                        break;

diff --git a/flags.h b/flags.h
index b157822a0a3295e974d2d18bd2f4725b7328ecb4..0f27cf205b749558ab342bd5344491677619ceb8 100644 (file)
--- a/flags.h
+++ b/flags.h
@@ -19,6 +19,9 @@ struct Flags {
        int stream_audio_codec_bitrate = DEFAULT_AUDIO_OUTPUT_BIT_RATE;  // Ignored if stream_audio_codec_name is blank.
        std::string x264_preset = X264_DEFAULT_PRESET;
        std::string x264_tune = X264_DEFAULT_TUNE;
+       int x264_bitrate = DEFAULT_X264_OUTPUT_BIT_RATE;  // In kilobit/sec.
+       int x264_vbv_max_bitrate = -1;  // In kilobits. 0 = no limit, -1 = same as <x264_bitrate> (CBR).
+       int x264_vbv_buffer_size = -1;  // In kilobits. 0 = one-frame VBV, -1 = same as <x264_bitrate> (one-second VBV).
 };
 extern Flags global_flags;
 

diff --git a/x264_encoder.cpp b/x264_encoder.cpp
index bbbb1ba33df907babd72c9f2a9c91d1596950936..feec9da9a7c1739932393c83705adbea12a391c7 100644 (file)
--- a/x264_encoder.cpp
+++ b/x264_encoder.cpp
@@ -76,13 +76,19 @@ void X264Encoder::init_x264()
        param.vui.i_transfer = 2;  // Unspecified (since we use sRGB).
        param.vui.i_colmatrix = 6;  // BT.601/SMPTE 170M.
 
-       // 4.5 Mbit/sec, CBR.
-       param.rc.i_rc_method = X264_RC_ABR;
-       param.rc.i_bitrate = 4500;
 
-       // One-second VBV.
-       param.rc.i_vbv_max_bitrate = 4500;
-       param.rc.i_vbv_buffer_size = 4500;
+       param.rc.i_rc_method = X264_RC_ABR;
+       param.rc.i_bitrate = global_flags.x264_vbv_max_bitrate;
+       if (global_flags.x264_vbv_buffer_size < 0) {
+               param.rc.i_vbv_buffer_size = param.rc.i_bitrate;  // One-second VBV.
+       } else {
+               param.rc.i_vbv_buffer_size = global_flags.x264_vbv_buffer_size;
+       }
+       if (global_flags.x264_vbv_max_bitrate < 0) {
+               param.rc.i_vbv_max_bitrate = param.rc.i_bitrate;  // CBR.
+       } else {
+               param.rc.i_vbv_max_bitrate = global_flags.x264_vbv_max_bitrate;
+       }
 
        // TODO: more flags here, via x264_param_parse().