JackLau1222
commented
4 days ago First, I think the meaning of pts and timestamp in BMF is the same as in FFmpeg , but bmf_sdk::Packet is more like a general data structure, it can pack any data, so if you want to use the variable, you need to set the timestamp every time you create a bmf_sdk::Packet , so the timestamp defaults to -1.
Second, the VideoFrame is just like AVFrame in FFmpeg, this data structure is used to pack various Frame from different video frame like ffmpeg or cuda.
For example, the pts is same as AVFrame in ffmpeg_decoder and ffmpeg_encoder module. you can see the details:
> grep -r "set_pts"
...
./c_modules/src/ffmpeg_decoder.cpp: video_frame.set_pts(frame->pts);
./c_modules/src/ffmpeg_decoder.cpp: audio_frame.set_pts(frame->pts);
./c_modules/src/ffmpeg_decoder.cpp: av_packet.set_pts(pkt->pts);
./c_modules/src/ffmpeg_decoder.cpp: video_frame.set_pts(frame->pts); // sync with avframe
./c_modules/src/ffmpeg_decoder.cpp: audio_frame.set_pts(frame->pts); // sync with avframe
./c_modules/src/ffmpeg_decoder.cpp: bmf_av_packet.set_pts(av_packet->pts); // sync with AVPacket
./c_modules/src/ffmpeg_decoder.cpp: bmf_pkt.set_pts((int64_t)BMF_EOF);
./c_modules/src/ffmpeg_decoder.cpp: bmf_pkt.set_pts(BMF_EOF);
./c_modules/src/ffmpeg_filter.cpp: video_frame.set_pts(frame->pts);
./c_modules/src/ffmpeg_filter.cpp: audio_frame.set_pts(frame->pts);
./c_modules/src/ffmpeg_encoder.cpp: video_frame.set_pts(frame->pts);
...
How to understand the pts in VideoFrame and the timestamp of Packet? I have a 30fps video.In generateMode, VideoFrame timebase 1 / 19200, pts increments 1280 or 1920, and the timestamp is always -1