> I have tried the following commands > > ffmpeg -err_detect ignore_err -i old.mp4 -c copy new.mp4 > ... > [mov,mp4,m4a,3gp,3g2,mj2 @ 00158b00] stream 1, contradictionary STSC and > STCO > [mov,mp4,m4a,3gp,3g2,mj2 @ 00158b00] error reading header
Hmm, I see. Maybe one last "cheap" attempt: if you are sure the issue is at the end, did you try the -t option? There's a slight chance you might recover most of the video... Now if that doesn't work, I'd rather concentrate on the root cause notified by ffmpeg: "contradictionary STSC and STCO". You might want to analyze that issue further (using either open-source software or trial of non-free products such as https://www.jongbel.com/manual-analysis/atombox-studio/ ) and then fix the issue by hand. - STSC is the sample-to-chunk table and can be used to find the chunk that contains a given sample - STCO is the chunk offset table and gives the index of each chunk into the file. Of course they must be consistent (e.g. STSC must reference chunks that exist in STCO, STCO indices must be < file size, etc.). Probably fixing those tables would make the file readable (even if incomplete). The Mpeg4 specification is licensed, but if you can get hold of it, the section that explains the structure of the ISO base media file format (ISO-BMFF) is "ISO_IEC_14496-12_2015.pdf" (or later). Alternatively, chatGPT is surprisingly good at explaining the ISOBMFF structure. There are many libraries that can help you either decode/edit the file or just understand its structure. For example: C: https://wiki.gpac.io/MP4Box/MP4Box Javascript: https://github.com/gpac/mp4box.js Rust: https://github.com/mozilla/mp4parse-rust Python: https://github.com/essential61/mp4analyser Java: https://github.com/sannies/mp4parser and many others. I personally used the last one because I have a Java background. It's not perfect but allows you to read, modify and write mp4 files. It might crash on inconsistencies in the file, but you are always free to change the code and handle these cases if needed. Hope it helps Vincent . _______________________________________________ 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".
