10MB mp4 with header corruption/bug (from audacityteam)

[esco1]

A 10MB of an mp4 audio file is corrupted: a member of audacity team suggest me to post the problem in this forum: I hope it is possible to remove the bug and recover the mp4 audio file.

Audio mp4 file is recorded with a nokia phone 6220c, the audio mp4 record with the bug is an important interview: other mp4 files recorded in the same way sound really good.

I can send a not corrupted mp4 file and the corrupted mp4 file, to compare both files recorded with the same system.

I tried looking in a Hex editor and a few conversion and MP4 analysis/repair tools without getting enough data to repair, but I am not an expert, nor do we undertake to repair broken files. It seems there is sufficient header information that the file is recognised as an AAC file, but the data can't be worked with.

:helpful:


following the Audacity Log


> 13:21:02: Opening with libav
> 13:21:02: Log: [mov,mp4,m4a,3gp,3g2,mj2 @ 649E1258] moov atom not found
> 13:21:02: FFmpeg : av_open_input_file() failed for file E:\file.mp4
> 13:21:02: Opening failed.
>
> mp4muxer
> ReadChildAtoms: of root
> ReadAtom: pos = 0x0
> ReadAtom: type = "ftyp" data-size = 20 (0x14) hdr 8
> Read: majorBrand = mp42
> Read: minorVersion = 0 (0x00000000)
> Read: compatibleBrandsCount = 3 (0x00000003)
> ReadAtom: pos = 0x1c
> ReadAtom: type = "mdat" data-size = 11325404 (0xaccfdc) hdr 8
> Skip: 11325404 bytes
> Warning: In atom missing child atom moov
> ReadChildAtoms: finished
> MP4ERROR: MP4File::FindIntegerProperty: no such property - moov.mvhd.modificationTime

[esco1]

Other info:

- Quick Time don't open the mp4 clip becouse "it is not a movies", (it can open other similar mp4 clip).

- Mpeg Streamclip don't open the mp4 clip becouse "file unknowed", (it can open other similar mp4 clip). With the option "Open anyway" it show "Error Opening file: "it is not possible to find video or audio tracks".

- VLC show the following answer:

main debug: CPU has capabilities AltiVec FPU
main debug: looking for memcpy module: 2 candidates
main debug: using memcpy module "memcpyaltivec"
main debug: waiting for thread completion
main debug: thread 25193984 (playlist) created at priority -47 (playlist/playlist.c:184)
main debug: waiting for thread completion
main debug: thread 26137088 (preparser) created at priority -47 (playlist/playlist.c:210)
main debug: looking for interface module: 1 candidate
main debug: using interface module "hotkeys"
main debug: thread 26150400 (interface) created at priority -47 (interface/interface.c:198)
main debug: looking for interface module: 3 candidates
main debug: using interface module "macosx"
main debug: thread 26143744 (manage) created at priority -47 (interface/interface.c:164)
main debug: adding playlist item `MP + MC' ( /Users/fc/Movies/MP + MC.mp4 )
main debug: creating new input thread
main debug: waiting for thread completion
main debug: thread 26673664 (input) created at priority 37 (input/input.c:261)
main debug: creating statistics handler
main debug: `/Users/fc/Movies/MP + MC.mp4' gives access `' demux `' path `/Users/fc/Movies/MP + MC.mp4'
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access_demux module: 1 candidate
macosx debug: input has changed, refreshing interface
main debug: creating access '' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access2 module: 7 candidates
vcd debug: trying .cue file: /Users/fc/Movies/MP + MC.cue
access_file debug: opening file `/Users/fc/Movies/MP + MC.mp4'
main debug: using access2 module "access_file"
main debug: pre-buffering...
main debug: received first data for our buffer
main debug: pre-buffering done 1408981 bytes in 0s - 238261 kbytes/s
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for demux2 module: 43 candidates
mp4 debug: found Box: ftyp size 28
mp4 debug: found an empty box (null size)
mp4 debug: dumping root Box "root"
mp4 debug: | + ftyp size 28
mp4 debug: unrecognized major file specification (mp42).
mp4 error: MP4 plugin discarded (no moov box)
ffmpeg debug: detected format: mov,mp4,m4a,3gp,3g2,mj2
access_file error: seeking too far
access_file error: seeking too far
ffmpeg debug: AVFormat supported stream
ffmpeg debug: - format = mov,mp4,m4a,3gp,3g2,mj2 (QuickTime/MPEG4/Motion JPEG 2000 format)
ffmpeg debug: - start time = -1
ffmpeg debug: - duration = -1
main debug: using demux2 module "ffmpeg"
main debug: looking for a subtitle file in /Users/fc/Movies/
main debug: `/Users/fc/Movies/MP + MC.mp4' successfully opened
main debug: EOF reached
macosx debug: input has stopped, refreshing interface
main debug: closing input
main debug: removing module "ffmpeg"
main debug: removing module "access_file"
main debug: thread 26673664 joined (input/input.c:399)
main: nothing to play
main debug: creating new input thread
main debug: waiting for thread completion
main debug: thread 26758144 (input) created at priority 37 (input/input.c:261)
main debug: `/Users/fc/Movies/MP + MC.mp4' gives access `' demux `' path `/Users/fc/Movies/MP + MC.mp4'
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access_demux module: 1 candidate
main debug: creating access '' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access2 module: 7 candidates
vcd debug: trying .cue file: /Users/fc/Movies/MP + MC.cue
access_file debug: opening file `/Users/fc/Movies/MP + MC.mp4'
main debug: using access2 module "access_file"
main debug: pre-buffering...
main debug: received first data for our buffer
main debug: pre-buffering done 1408981 bytes in 0s - 271445 kbytes/s
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for demux2 module: 43 candidates
mp4 debug: found Box: ftyp size 28
mp4 debug: found an empty box (null size)
mp4 debug: dumping root Box "root"
mp4 debug: | + ftyp size 28
mp4 debug: unrecognized major file specification (mp42).
mp4 error: MP4 plugin discarded (no moov box)
ffmpeg debug: detected format: mov,mp4,m4a,3gp,3g2,mj2
access_file error: seeking too far
access_file error: seeking too far
ffmpeg debug: AVFormat supported stream
ffmpeg debug: - format = mov,mp4,m4a,3gp,3g2,mj2 (QuickTime/MPEG4/Motion JPEG 2000 format)
ffmpeg debug: - start time = -1
ffmpeg debug: - duration = -1
main debug: using demux2 module "ffmpeg"
main debug: looking for a subtitle file in /Users/fc/Movies/
main debug: `/Users/fc/Movies/MP + MC.mp4' successfully opened
main debug: EOF reached
macosx debug: input has changed, refreshing interface
main debug: closing input
main debug: removing module "ffmpeg"
main debug: removing module "access_file"
macosx debug: input has stopped, refreshing interface
main debug: thread 26758144 joined (input/input.c:399)
main: nothing to play
main debug: creating new input thread
main debug: waiting for thread completion
main debug: thread 26859520 (input) created at priority 37 (input/input.c:261)
main debug: `/Users/fc/Movies/MP + MC.mp4' gives access `' demux `' path `/Users/fc/Movies/MP + MC.mp4'
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access_demux module: 1 candidate
main debug: creating access '' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access2 module: 7 candidates
vcd debug: trying .cue file: /Users/fc/Movies/MP + MC.cue
access_file debug: opening file `/Users/fc/Movies/MP + MC.mp4'
main debug: using access2 module "access_file"
main debug: pre-buffering...
main debug: received first data for our buffer
main debug: pre-buffering done 1408981 bytes in 0s - 328783 kbytes/s
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for demux2 module: 43 candidates
mp4 debug: found Box: ftyp size 28
mp4 debug: found an empty box (null size)
mp4 debug: dumping root Box "root"
mp4 debug: | + ftyp size 28
mp4 debug: unrecognized major file specification (mp42).
mp4 error: MP4 plugin discarded (no moov box)
ffmpeg debug: detected format: mov,mp4,m4a,3gp,3g2,mj2
access_file error: seeking too far
access_file error: seeking too far
ffmpeg debug: AVFormat supported stream
ffmpeg debug: - format = mov,mp4,m4a,3gp,3g2,mj2 (QuickTime/MPEG4/Motion JPEG 2000 format)
ffmpeg debug: - start time = -1
ffmpeg debug: - duration = -1
main debug: using demux2 module "ffmpeg"
main debug: looking for a subtitle file in /Users/fc/Movies/
main debug: `/Users/fc/Movies/MP + MC.mp4' successfully opened
main debug: EOF reached
macosx debug: input has changed, refreshing interface
main debug: closing input
main debug: removing module "ffmpeg"
main debug: removing module "access_file"
main debug: thread 26859520 joined (input/input.c:399)
main: nothing to play
macosx debug: input has stopped, refreshing interface
main debug: creating new input thread
main debug: waiting for thread completion
main debug: thread 26909696 (input) created at priority 37 (input/input.c:261)
main debug: `/Users/fc/Movies/MP + MC.mp4' gives access `' demux `' path `/Users/fc/Movies/MP + MC.mp4'
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access_demux module: 1 candidate
main debug: creating access '' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for access2 module: 7 candidates
vcd debug: trying .cue file: /Users/fc/Movies/MP + MC.cue
access_file debug: opening file `/Users/fc/Movies/MP + MC.mp4'
main debug: using access2 module "access_file"
main debug: pre-buffering...
main debug: received first data for our buffer
main debug: pre-buffering done 1408981 bytes in 0s - 463910 kbytes/s
main debug: creating demux: access='' demux='' path='/Users/fc/Movies/MP + MC.mp4'
main debug: looking for demux2 module: 43 candidates
mp4 debug: found Box: ftyp size 28
mp4 debug: found an empty box (null size)
mp4 debug: dumping root Box "root"
mp4 debug: | + ftyp size 28
mp4 debug: unrecognized major file specification (mp42).
mp4 error: MP4 plugin discarded (no moov box)
ffmpeg debug: detected format: mov,mp4,m4a,3gp,3g2,mj2
access_file error: seeking too far
access_file error: seeking too far
ffmpeg debug: AVFormat supported stream
ffmpeg debug: - format = mov,mp4,m4a,3gp,3g2,mj2 (QuickTime/MPEG4/Motion JPEG 2000 format)
ffmpeg debug: - start time = -1
ffmpeg debug: - duration = -1
main debug: using demux2 module "ffmpeg"
main debug: looking for a subtitle file in /Users/fc/Movies/
main debug: `/Users/fc/Movies/MP + MC.mp4' successfully opened
main debug: EOF reached
macosx debug: input has changed, refreshing interface
main debug: closing input
main debug: removing module "ffmpeg"
main debug: removing module "access_file"
main debug: thread 26909696 joined (input/input.c:399)
main: nothing to play
macosx debug: input has stopped, refreshing interface

[Shirtfull]

Since you've mentioned using a Hex editor, try appending the bad file to the end of a working audio file.

[esco1]

Shirtfull, I will try.