sharpbai
6966548c1b
On iOS 11, encoding a frame may return error with log "Error encoding frame 0", which means vtenc_output_callback is called with status=0 and sample_buffer=NULL. Then the encoding session will be crashed on next callback wether or not closing the codec context. Let us look through the link below introducing VTCompressionOutputCallback, https://developer.apple.com/documentation/videotoolbox/vtcompressionoutputcallback?language=objc "status=0" (noErr) means compression was successful. "sampleBuffer=NULL" means the frame was dropped when compression was successful (status=0) or compression was not successful (status!=0). So we should not set AVERROR_EXTERNAL on "status=0" and "sample_buffer=NULL" as it is not a error. The fix is that we only set AVERROR_EXTERNAL with status value non zero. When sample_buffer is NULL and status value is zero, we simply return with no other operation. This crash often occurs on iOS 11 for example encoding 720p@25fps. Signed-off-by: sharpbai <sharpbai@gmail.com> Signed-off-by: Rick Kern <kernrj@gmail.com>
FFmpeg README
FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata.
Libraries
libavcodecprovides implementation of a wider range of codecs.libavformatimplements streaming protocols, container formats and basic I/O access.libavutilincludes hashers, decompressors and miscellaneous utility functions.libavfilterprovides a mean to alter decoded Audio and Video through chain of filters.libavdeviceprovides an abstraction to access capture and playback devices.libswresampleimplements audio mixing and resampling routines.libswscaleimplements color conversion and scaling routines.
Tools
- ffmpeg is a command line toolbox to manipulate, convert and stream multimedia content.
- ffplay is a minimalistic multimedia player.
- ffprobe is a simple analysis tool to inspect multimedia content.
- Additional small tools such as
aviocat,ismindexandqt-faststart.
Documentation
The offline documentation is available in the doc/ directory.
The online documentation is available in the main website and in the wiki.
Examples
Coding examples are available in the doc/examples directory.
License
FFmpeg codebase is mainly LGPL-licensed with optional components licensed under GPL. Please refer to the LICENSE file for detailed information.
Contributing
Patches should be submitted to the ffmpeg-devel mailing list using
git format-patch or git send-email. Github pull requests should be
avoided because they are not part of our review process and will be ignored.