Re: [FFmpeg-user] FFmpeg audio frame count/nb_samples misunderstanding?
True. Having multiple -f options on the output section of the ffmpeg sender command line is unnecessary and has been adjusted since originally posted. Only the last one takes effect, but doesn't trigger an error. -- Sent from: http://www.ffmpeg-archive.org/ ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
Re: [FFmpeg-user] FFmpeg audio frame count/nb_samples misunderstanding?
After discussing with support within the #ffmpeg IRC channel, this approach doesn't seem to be too reliable or consistent to keep track of frame count from sender and receiver. A "frame" in ffmpeg at the decoding side is just "however many samples the decoder decoded from one packet". The thing with the audio the audio formats have packets that contain frames of differing size so input and outputs can differ in count. It was recommended that if 100% sure that receiver will get all packets, then I should check the count of packets fed to muxer, and then the count of packets read from demuxer, those in theory should match. How ever on the reciever end it was always missign a couple of packets that were not repeated. This could be depended on how the sender was stopped, it might be possible that there was some audio that passed through the filter chain but didn't get encoded/sent. -- Sent from: http://www.ffmpeg-archive.org/ ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
[FFmpeg-user] FFmpeg audio frame count/nb_samples misunderstanding?
I am streaming audio between two linux machines using ffmpeg and ffplay. The sender is using rtsp to transport audio using a USB microphone over TCP. The receiver (listener) is receiving and playing the audio received using ffplay. Sending: Receiving(listening): Using /‘ashowinfo’/, I am able to see a line containing various information for each input audio frame. The option /nostats/ is used to avoid other stats interleaved within the log output. “n” denotes the (sequential) number of the input frame, starting from 0. The receiver and sender are both using the /-af/ option flag to see the frame counts. However when the stream ends, the audio frame numbers are completely off as shown below. I have searched before, but have not seen any specific or technical algorithm that ffmpeg uses to justify how frame counts are defined. Also I am not sure why my sender with the microphone audio has various nb_sample sizes with each frame increment? I have noticed that the audio streamed from rtsp is always received as having each frame with "nb_sample" of 1024. I have tried adding the /frame_size/ option but with no change in consistent number of samples per frame input for the sender. The aim is to have a consist method to correlate where the sender and receiver are at once the audio stream has been stopped. Below are the log files outputted for each command with their respective machines: Sending log: Receiving log: -- Sent from: http://www.ffmpeg-archive.org/ ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
