Hello, We are trying to understand two fields in AVCodecParameters: bits_per_coded_sample and bits_per_raw_sample.
In the comments in libavcodec/avcodec.h, bits_per_coded_sample is described as "the bitrate per sample". This sounds like (encoded bitrate / sample rate), for example 128 kbps 44.1 kHz audio stream would be 3 bits per coded audio sample. But, the code usage suggests that this field is actually "the bit depth of each sample, if the sample was uncompressed", which is also similar to the comments and usage for bits_per_raw_sample. For example, the mov.c demuxing initializes bits_per_coded_sample when parsing the "sample size" field of the mp4 AudioSampleEntry (in the stsd atom, for both audio and video). Various codecs/formats initialize one value, or the other, or both in different times. For example, pcm.c audio codec sets bits_per_coded_sample on encoding, and bits_per_raw_sample on decoding. But the mov.c demuxer and movenc.c muxer both use bits_per_coded_sample for muxing. So, what really is the difference between these two values? Is it possible that these fields should just be merged into one field? Or if there is a pattern we don't see, perhaps only the comments need to be updated? Best Regards, Shawn Singh _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
