[M4IF Technotes] The content in the DecoderSpecificInfo
Dave Singer
singer apple.com
Tue Sep 17 11:10:27 EDT 2002
At 09:28 -0700 9/17/02, Heat Mist wrote:
>--- Jean-Claude Dufourd <Jean-Claude.Dufourd enst.fr>
>wrote:
>> Heat Mist wrote:
>> > Yes, I downloaded a few mp4 files that contain
>> video
>> > and/or audio. I haven't checked all of them. But
>> the
>> > file called 4videomaxmin_light.mp4 from "MPEG-4
>> > Content" link on ENST doesn't follow the visual
>> > DecoderSpecificInfo syntax defined in 14496-2.
>>
>> Can you please be specific about the error ? This
>> file works seamlessly
>> with the TILAB/Optibase player, with the Envivio
>> player, with the IM1-2D
>> player. I feel confident that the error is minor if
>> all these players
>> accept that content without problem.
>>
>
>In the 4 ES_Descriptors within the esds atom of mp4v
>stream, the DecoderSpecificInfo of the
>DecoderConfigDescriptor doesn't contain
>VisualObjectSequence(). (Shouldn't it? In 14496-2
>Annex K: "VisualObjectSequence() is transmitted
>explicitly in each DecConfigDescr.DecSpecificInfo of
>an Object Descriptor".)
>
>chen
Yes, I think it should. Here is a dump of the first track that I
found with MPEG-4 video in it (the first video track has JPEG in it).
The decoder-specific-info seems to start with a VOL, whereas strictly
I think a VOSH is needed (see next example).
[I'm dumping some fields here which are reserved in MP4, please don't
get confused by that.]
trak trak
udta udta
tkhd tkhd
mdia mdia
mdhd mdhd
hdlr hdlr
minf minf
dinf dinf
dref dref
vmhd vmhd
stbl stbl
stts stts
stsd stsd
version 0
flags 000000
sdNumEntries 1
1 SdEntry
sdSize 143
sdType mp4v
datRefIndex 1
version 0000
revision 0000
vendor ××××
tempquality 00000000
spatialquality 00000000
videowidth 0
videoheight 0
horiz_res 4718592 72.000000
vert_res 4718592 72.000000
datasize 00000000
framecount 0001
compressorname ×MPEG-4 Visual
videodepth 0018
videoclutID -1
struct
esds esds
version 0
flags 000000
Descr size 42
esd esd
ES_ID 0000
streamdependenceflŠ0
URL_flag 0
OCRStreamFlag 0
streampriority 10
Descr size 33
decoderconfig decconf
objectType 20
streamtype 04
upstream 0
reserved 1
buffersize 0014D8
maxbitrate 00000000
avgBitrate 00000000
Descr size 18
dec_specific dec_specific
v_start_code 01
VID_OBJ struct
v_start_code 20
VOL struct
random_acc_vol 0
vid_o_type 04
is_OL_ID 0
aspect_ratio_iŠ1
vol_ctrl_par 1
chroma_f 1
lo_delay 1
vbv_par 0
vol_shape 0
VOP_TimeInc_res000A
fixed_VOP_rate 0
vol_width 160
vol_height 120
interlaced 0
obmc_disable 1
sprite_enable 0
not_8_bit 0
quant_type 0
complex_est_diŠ1
resynch_mkr_dis0
data_partitionŠ0
v_scalability 0
Descr size 1
slconfigdescr slconfigdesc
predefined 02
stsz stsz
stsc stsc
stss stss
stco stco
Here's one with all the layers in it:
trak trak
tkhd tkhd
edts edts
elst elst
mdia mdia
mdhd mdhd
hdlr hdlr
minf minf
vmhd vmhd
dinf dinf
dref dref
stbl stbl
stsd stsd
version 0
flags 000000
sdNumEntries 1
1 SdEntry
sdSize 155
sdType mp4v
datRefIndex 1
version 0000
revision 0000
vendor 00000000
tempquality 00000000
spatialquality 00000000
videowidth 320
videoheight 240
horiz_res 4718592 72.000000
vert_res 4718592 72.000000
datasize 00000000
framecount 0001
compressorname ×
videodepth 0018
videoclutID -1
esds esds
version 0
flags 000000
Descr size 55
esd esd
ES_ID 0000
streamdependenceflag0
URL_flag 0
OCRStreamFlag 0
streampriority 1F
Descr size 47
decoderconfig decconf
objectType 20
streamtype 04
upstream 0
reserved 1
buffersize 001000
maxbitrate 00001000
avgBitrate 00001000
Descr size 32
dec_specific dec_specific
v_start_code B0
VOSH struct
v_profile F3
v_start_code B5
VO struct
is_v_OID 0
vis_o_type 1
v_signal_type 1
video_format 5
video_range 1
colour_desc 1
colour_primaries02
transfer_char 06
matrix_coeff 06
v_start_code 00
VID_OBJ struct
v_start_code 20
VOL struct
random_acc_vol0
vid_o_type 01
is_OL_ID 0
aspect_ratio_Š1
vol_ctrl_par 0
vol_shape 0
VOP_TimeInc_rŠ001E
fixed_VOP_rate0
vol_width 320
vol_height 240
interlaced 0
obmc_disable 1
sprite_enable 0
not_8_bit 0
quant_type 0
complex_est_dŠ1
resynch_mkr_dŠ0
data_partitioŠ0
v_scalability 0
Descr size 1
slconfigdescr slconfigdesc
predefined 02
stts stts
stss stss
stsc stsc
stsz stsz
stco stco
--
David Singer
Apple Computer/QuickTime
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