Hi. I'm having an issue with MediaConvert. Running a fairly simple job on what seems like a rather unremarkable H.264 MP4 is resulting in sync issues between audio and video in the output. The sync starts out okay, but by the end of the output video it is noticeably off.
Here's the MediaInfo output for the input MP4:
General
Count : 331
Count of stream of this kind : 1
Kind of stream : General
Kind of stream : General
Stream identifier : 0
Count of video streams : 1
Count of audio streams : 1
Video_Format_List : AVC
Video_Format_WithHint_List : AVC
Codecs Video : AVC
Audio_Format_List : AAC LC
Audio_Format_WithHint_List : AAC LC
Audio codecs : AAC LC
Complete name : 59397af7-aba0-4b8f-ac14-4c351ec69688.mp4
File name extension : 59397af7-aba0-4b8f-ac14-4c351ec69688.mp4
File name : 59397af7-aba0-4b8f-ac14-4c351ec69688
File extension : mp4
Format : MPEG-4
Format : MPEG-4
Format/Extensions usually used : braw mov mp4 m4v m4a m4b m4p m4r 3ga 3gpa 3gpp 3gp 3gpp2 3g2 k3g jpm jpx mqv ismv isma ismt f4a f4b f4v
Commercial name : MPEG-4
Format profile : Base Media
Internet media type : video/mp4
Codec ID : isom
Codec ID : isom (isom/iso2/avc1/mp41)
Codec ID/Url : http://www.apple.com/quicktime/download/standalone.html
CodecID_Compatible : isom/iso2/avc1/mp41
File size : 11085451
File size : 10.6 MiB
File size : 11 MiB
File size : 11 MiB
File size : 10.6 MiB
File size : 10.57 MiB
Duration : 297434
Duration : 4 min 57 s
Duration : 4 min 57 s 434 ms
Duration : 4 min 57 s
Duration : 00:04:57.434
Duration : 00:04:57:13
Duration : 00:04:57.434 (00:04:57:13)
Overall bit rate mode : VBR
Overall bit rate mode : Variable
Overall bit rate : 298162
Overall bit rate : 298 kb/s
Frame rate : 30.000
Frame rate : 30.000 FPS
Frame count : 8923
Stream size : 328932
Stream size : 321 KiB (3%)
Stream size : 321 KiB
Stream size : 321 KiB
Stream size : 321 KiB
Stream size : 321.2 KiB
Stream size : 321 KiB (3%)
Proportion of this stream : 0.02967
HeaderSize : 40
DataSize : 10756527
FooterSize : 328884
IsStreamable : No
File last modification date : UTC 2021-04-12 10:12:36
File last modification date (local) : 2021-04-12 11:12:36
Writing application : Lavf57.83.100
Writing application : Lavf57.83.100
Video
Count : 378
Count of stream of this kind : 1
Kind of stream : Video
Kind of stream : Video
Stream identifier : 0
StreamOrder : 0
ID : 1
ID : 1
Format : AVC
Format : AVC
Format/Info : Advanced Video Codec
Format/Url : http://developers.videolan.org/x264.html
Commercial name : AVC
Format profile : High@L4
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, CABAC : Yes
Format settings, Reference frames : 4
Format settings, Reference frames : 4 frames
Internet media type : video/H264
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 297434
Duration : 4 min 57 s
Duration : 4 min 57 s 434 ms
Duration : 4 min 57 s
Duration : 00:04:57.434
Duration : 00:04:57:13
Duration : 00:04:57.434 (00:04:57:13)
Bit rate : 167254
Bit rate : 167 kb/s
Width : 1920
Width : 1 920 pixels
Height : 1080
Height : 1 080 pixels
Stored_Height : 1088
Sampled_Width : 1920
Sampled_Height : 1080
Pixel aspect ratio : 1.000
Display aspect ratio : 1.778
Display aspect ratio : 16:9
Rotation : 0.000
Frame rate mode : CFR
Frame rate mode : Constant
FrameRate_Mode_Original : VFR
Frame rate : 30.000
Frame rate : 30.000 FPS
Frame count : 8923
Color space : YUV
Chroma subsampling : 4:2:0
Chroma subsampling : 4:2:0
Bit depth : 8
Bit depth : 8 bits
Scan type : Progressive
Scan type : Progressive
Bits/(Pixel*Frame) : 0.003
Stream size : 6218374
Stream size : 5.93 MiB (56%)
Stream size : 6 MiB
Stream size : 5.9 MiB
Stream size : 5.93 MiB
Stream size : 5.930 MiB
Stream size : 5.93 MiB (56%)
Proportion of this stream : 0.56095
Writing library : x264 - core 152 r2854 e9a5903
Writing library : x264 core 152 r2854 e9a5903
Encoded_Library_Name : x264
Encoded_Library_Version : core 152 r2854 e9a5903
Encoding settings : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=23.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Codec configuration box : avcC
Audio
Count : 280
Count of stream of this kind : 1
Kind of stream : Audio
Kind of stream : Audio
Stream identifier : 0
StreamOrder : 1
ID : 2
ID : 2
Format : AAC
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Commercial name : AAC
Format settings, SBR : No (Explicit)
Format settings, SBR : No (Explicit)
Format_AdditionalFeatures : LC
Codec ID : mp4a-40-2
Duration : 297340
Duration : 4 min 57 s
Duration : 4 min 57 s 340 ms
Duration : 4 min 57 s
Duration : 00:04:57.340
Duration : 00:04:56:00
Duration : 00:04:57.340 (00:04:56:00)
Bit rate mode : VBR
Bit rate mode : Variable
Bit rate : 122099
Bit rate : 122 kb/s
Maximum bit rate : 128000
Maximum bit rate : 128 kb/s
Channel(s) : 2
Channel(s) : 2 channels
Channel positions : Front: L R
Channel positions : 2/0/0
Channel layout : L R
Samples per frame : 1024
Sampling rate : 48000
Sampling rate : 48.0 kHz
Samples count : 14272320
Frame rate : 46.875
Frame rate : 46.875 FPS (1024 SPF)
Frame count : 13912
Compression mode : Lossy
Compression mode : Lossy
Stream size : 4538145
Stream size : 4.33 MiB (41%)
Stream size : 4 MiB
Stream size : 4.3 MiB
Stream size : 4.33 MiB
Stream size : 4.328 MiB
Stream size : 4.33 MiB (41%)
Proportion of this stream : 0.40938
Title : simple_aac
Default : Yes
Default : Yes
Alternate group : 1
Alternate group : 1
And the MediaConvert job description (ID: 1618087025011-n9fbdn, in case anyone from AWS is reading):
{
"Queue": "[removed]",
"UserMetadata": {
"contentItemId": "[removed]",
"mode": "preview",
"environment": "production"
},
"Role": "[removed]",
"Settings": {
"OutputGroups": [
{
"CustomName": "File Group",
"Outputs": [
{
"ContainerSettings": {
"Container": "MP4",
"Mp4Settings": {}
},
"VideoDescription": {
"Width": 1920,
"Height": 1080,
"CodecSettings": {
"Codec": "H_264",
"H264Settings": {
"MaxBitrate": 6000000,
"RateControlMode": "QVBR",
"QvbrSettings": {
"QvbrQualityLevel": 9
}
}
}
},
"AudioDescriptions": [
{
"CodecSettings": {
"Codec": "AAC",
"AacSettings": {
"VbrQuality": "MEDIUM_HIGH",
"RateControlMode": "VBR",
"CodingMode": "CODING_MODE_2_0",
"SampleRate": 48000
}
}
}
],
"NameModifier": "-preview"
}
],
"OutputGroupSettings": {
"Type": "FILE_GROUP_SETTINGS",
"FileGroupSettings": {
"Destination": "[removed]"
}
}
}
],
"Inputs": [
{
"AudioSelectors": {
"Audio Selector 1": {
"SelectorType": "TRACK"
}
},
"FileInput": "[removed]"
}
]
},
"AccelerationSettings": {
"Mode": "DISABLED"
},
"StatusUpdateInterval": "SECONDS_60",
"Priority": 0
}