Hi,
Morfsta schrieb:
OK, I have added the following code into src/demuxers/demux_mpeg_pes.c
static int32_t GetVideoSize(const uint8_t *buf, int length, int *width, int *height) { int i = 0; // the minimum length of the video packet header //i += buf[i] + 1; // possible additional header bytes for (; i < length-6; i++) { if (buf[i] == 0 && buf[i + 1] == 0 && buf[i + 2] == 1) { if(buf[i + 3] == 0xb3) { int d = (buf[i+4] << 16) | (buf[i+5] << 8) | buf[i+6]; *width = (d >> 12); *height = (d & 0xfff); return 1; } } } return 0; }
and then put the following code in parse_video_stream: -
int Width, Height; if (GetVideoSize(p, payload_size, &Width, &Height)) { printf("Detected video size %dx%d\n", Width, Height); } else { printf("Failed to detect video size\n"); }
before: /* H.264 broadcasts via DVB-S use standard video PES packets,
This detects the video size for MPEG2 broadcasts (Detected video size 704x576 ), but not for H264, I'm guessing the payload is in a different format. Can anyone point me in the direction of a GetVideoSize type of function for H264 (I looked in libavcodec and the code looks a bit more complex!), or spot what I am doing wrong here?
In H.264, this information in coded far more complex. Have a look into VDR's h264parser.c. Look for pic_width_in_mbs_minus1, pic_height_in_map_units_minus1 and frame_crop_*_offset.
You can get the standard from here for free: http://www.itu.int/rec/T-REC-H.264-200503-I/en
Bye.