Problem on playing alaw in mp4 file

[BrainLai]

Dear all:

I am sure VLC can play alaw locally from an RTSP session. However, if I save the stream as an mp4 file, it cannot be palyed anymore.

Two problems listed below:

1. why does not VLC support to save alaw in mp4 file?

In the message dialog, it says:

mux_mp4 error: unsupported codec alaw in mp4
main error: cannot add this stream

2. due to problem 1, I apply live555.com's library class QuickTimeFileSink to save alaw in an mp4 file. But it cannot be played as it should be. Who can tell me what's wrong and how to correct it?

The message dialog says:

main debug: adding playlist item `/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4' ( /home/BrainLai/media/demo-2006-3-21-14-19-20.mp4 )
main debug: creating new input thread
main debug: waiting for thread completion
main debug: thread 55204784 (input) created at priority 0 (src/input/input.c:230)
main debug: `/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4' gives access `' demux `' path `/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4'
main debug: creating demux: access='' demux='' path='/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4'
main debug: looking for access_demux module: 2 candidates
main debug: creating access '' path='/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4'
main debug: looking for access2 module: 5 candidates
vcd debug: trying .cue file: /home/BrainLai/media/demo-2006-3-21-14-19-20.cue
access_file debug: opening file `/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4'
main debug: using access2 module "access_file"
main debug: pre buffering
main debug: received first data for our buffer
main debug: creating demux: access='' demux='' path='/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4'
main debug: looking for demux2 module: 40 candidates
mp4 debug: found Box: ftyp size 24
mp4 debug: found Box: moov size 1046
mp4 debug: found Box: mvhd size 108
mp4 debug: read box: "mvhd" creation 732311d-46h:19m:24s modification 732312d-54h:19m:24s time scale 8000 duration 694977d-48h:00m:00s rate 1.000000 volume 1.000000 next track id 3
mp4 debug: found Box: iods size 24
mp4 warning: unknown box type iods (uncompletetly loaded)
mp4 debug: found Box: trak size 501
mp4 debug: found Box: tkhd size 92
mp4 debug: read box: "tkhd" creation 732311d-46h:19m:24s modification 732311d-46h:19m:24s duration -1510497220d-30h:13m:20s track ID 1 layer 0 volume 1.000000 width 0.000000 height 0.000000
mp4 debug: found Box: edts size 36
mp4 debug: found Box: elst size 28
mp4 debug: read box: "elst" entry-count 0
mp4 debug: found Box: mdia size 365
mp4 debug: found Box: mdhd size 32
mp4 debug: read box: "mdhd" creation 732311d-46h:19m:24s modification 732311d-46h:19m:24s time scale 8000 duration 694977d-03h:33m:20s language ```
mp4 debug: found Box: hdlr size 58
mp4 debug: read box: "hdlr" hanler type soun name pple Sound Media Handler
mp4 debug: found Box: minf size 267
mp4 debug: found Box: smhd size 16
mp4 debug: read box: "smhd" balance 0.000000
mp4 debug: found Box: hdlr size 57
mp4 debug: read box: "hdlr" hanler type alis name Apple Alias Data Handler
mp4 debug: found Box: dinf size 36
mp4 debug: found Box: dref size 28
mp4 debug: found Box: alis size 12
mp4 warning: unknown box type alis (uncompletetly loaded)
mp4 debug: read box: "dref" entry-count 1
mp4 debug: found Box: stbl size 150
mp4 debug: found Box: stsd size 50
mp4 debug: found Box: alaw size 34
mp4 warning: Not enough data
mp4 debug: read box: "stsd" entry-count 1
mp4 debug: found Box: stts size 24
mp4 debug: read box: "stts" entry-count 1
mp4 debug: found Box: stsc size 28
mp4 debug: read box: "stsc" entry-count 1
mp4 debug: found Box: stsz size 20
mp4 debug: read box: "stsz" sample-size 1 sample-count 56000
mp4 debug: found Box: stco size 20
mp4 debug: read box: "co64" entry-count 1
mp4 debug: found Box: trak size 405
mp4 debug: found Box: tkhd size 92
mp4 debug: read box: "tkhd" creation 732312d-54h:19m:24s modification 732312d-54h:19m:24s duration 694977d-48h:00m:00s track ID 2 layer 0 volume 0.000000 width 0.000000 height 0.000000
mp4 debug: found Box: mdia size 305
mp4 debug: found Box: mdhd size 32
mp4 debug: read box: "mdhd" creation 732312d-54h:19m:24s modification 732312d-54h:19m:24s time scale 1000 duration 694977d-48h:00m:00s language ```
mp4 debug: found Box: hdlr size 33
mp4 debug: read box: "hdlr" hanler type EVET name
mp4 debug: found Box: minf size 232
mp4 debug: found Box: nmhd size 12
mp4 debug: found Box: dinf size 36
mp4 debug: found Box: dref size 28
mp4 debug: found Box: url size 12
mp4 debug: read box: "url" url: (null)
mp4 debug: read box: "dref" entry-count 1
mp4 debug: found Box: stbl size 176
mp4 debug: found Box: stsd size 76
mp4 debug: found Box: mp4s size 60
mp4 debug: found Box: esds size 44
mp4 debug: found esds MPEG4ESDescr (27Bytes)
mp4 debug: found esds MP4DecConfigDescr (13Bytes)
mp4 debug: read box: "stsd" entry-count 1
mp4 debug: found Box: stts size 24
mp4 debug: read box: "stts" entry-count 1
mp4 debug: found Box: stsz size 20
mp4 debug: read box: "stsz" sample-size 12 sample-count 1
mp4 debug: found Box: stsc size 28
mp4 debug: read box: "stsc" entry-count 1
mp4 debug: found Box: stco size 20
mp4 debug: read box: "co64" entry-count 1
mp4 debug: found Box: mdat size 56020
mp4 debug: skip box: "mdat"
mp4 debug: dumping root Box "root"
mp4 debug: | + ftyp size 24
mp4 debug: | + moov size 1046
mp4 debug: | | + mvhd size 108
mp4 debug: | | + iods size 24
mp4 debug: | | + trak size 501
mp4 debug: | | | + tkhd size 92
mp4 debug: | | | + edts size 36
mp4 debug: | | | | + elst size 28
mp4 debug: | | | + mdia size 365
mp4 debug: | | | | + mdhd size 32
mp4 debug: | | | | + hdlr size 58
mp4 debug: | | | | + minf size 267
mp4 debug: | | | | | + smhd size 16
mp4 debug: | | | | | + hdlr size 57
mp4 debug: | | | | | + dinf size 36
mp4 debug: | | | | | | + dref size 28
mp4 debug: | | | | | | | + alis size 12
mp4 debug: | | | | | + stbl size 150
mp4 debug: | | | | | | + stsd size 50
mp4 debug: | | | | | | | + alaw size 34
mp4 debug: | | | | | | + stts size 24
mp4 debug: | | | | | | + stsc size 28
mp4 debug: | | | | | | + stsz size 20
mp4 debug: | | | | | | + stco size 20
mp4 debug: | | + trak size 405
mp4 debug: | | | + tkhd size 92
mp4 debug: | | | + mdia size 305
mp4 debug: | | | | + mdhd size 32
mp4 debug: | | | | + hdlr size 33
mp4 debug: | | | | + minf size 232
mp4 debug: | | | | | + nmhd size 12
mp4 debug: | | | | | + dinf size 36
mp4 debug: | | | | | | + dref size 28
mp4 debug: | | | | | | | + url size 12
mp4 debug: | | | | | + stbl size 176
mp4 debug: | | | | | | + stsd size 76
mp4 debug: | | | | | | | + mp4s size 60
mp4 debug: | | | | | | | | + esds size 44
mp4 debug: | | | | | | + stts size 24
mp4 debug: | | | | | | + stsz size 20
mp4 debug: | | | | | | + stsc size 28
mp4 debug: | | | | | | + stco size 20
mp4 debug: | + mdat size 56020
mp4 debug: unrecognized major file specification (mp42).
mp4 debug: find 2 tracks
mp4 warning: elst box found
mp4 debug: - [0] duration=7000ms media time=0ms) rate=1.0
mp4 debug: track[Id 0x1] read 1 chunk
mp4 debug: track[Id 0x1] read 56000 samples length:7s
main debug: selecting program id=0
mp4 debug: adding track[Id 0x1] audio (enable) language undef
mp4 debug: ignoring track[Id 0x2]
main debug: using demux2 module "mp4"
mp4 warning: DEMUX_GET_FPS unimplemented !!
main debug: looking for a subtitle file in /home/BrainLai/media/
main debug: looking for decoder module: 22 candidates
araw error: bad channels count (1-8)
ffmpeg debug: libavcodec initialized (interface 3277056 )
ffmpeg debug: ffmpeg codec (PCM ALAW) started
main debug: using decoder module "ffmpeg"
main debug: thread 113585072 (decoder) created at priority 0 (src/input/decoder.c:159)
main debug: `/home/BrainLai/media/demo-2006-3-21-14-19-20.mp4' successfully opened
mp4 debug: elst (0) gives 0ms (movie)-> 0ms (track)
mp4 debug: track[Id 0x1] does not provide Sync Sample Box (stss)
mp4 warning: recreate ES for track[Id 0x1]
ffmpeg debug: ffmpeg codec (PCM ALAW) stopped
main debug: unlocking module "ffmpeg"
main debug: thread 113585072 joined (src/input/decoder.c:191)
main debug: killing decoder fourcc `alaw', 1 PES in FIFO
main debug: Program doesn't contain anymore ES
main debug: looking for decoder module: 22 candidates
araw error: bad channels count (1-8)
ffmpeg debug: libavcodec already initialized
ffmpeg debug: ffmpeg codec (PCM ALAW) started
main debug: using decoder module "ffmpeg"
main debug: thread 113585072 (decoder) created at priority 0 (src/input/decoder.c:159)
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
ffmpeg warning: invalid channels count 27745
main debug: EOF reached
main debug: waiting decoder fifos to empty
ffmpeg warning: invalid channels count 27745
main debug: closing input
mp4 debug: freeing all memory
main debug: unlocking module "mp4"
main debug: unlocking module "access_file"
ffmpeg debug: ffmpeg codec (PCM ALAW) stopped
main debug: unlocking module "ffmpeg"
main debug: thread 113585072 joined (src/input/decoder.c:191)
main debug: killing decoder fourcc `alaw', 0 PES in FIFO
main debug: thread 55204784 joined (src/input/input.c:386)
main warning: Unable to find parent !
main: nothing to play


PS: VLC 0.8.4a on Fedora Core 4

Thanks ahead!
Brain Lai