MP4 with HE-AAC / LC

[Tom Saurus]

I run across mp4 files that have the HE-ACC/ LC codec and my LG Blu Ray player doesn't accept that audio format. I have in the past demuxed the audio and video and converted the audio to a different format that it will accept. I remuxed the audio and video but ended up with out of sync audio. I can of course play the original files before conversion on a computer media player such as VLC. If I re-encode the entire mp4 with both the video and the audio I can end up with a playable file that is in sync that will play both on the computer and the LG Blu Ray player. I have an LG Blu Ray player that is about four years old and I never upgraded the firmware. Does anyone know if LG has a Blu-Ray player that can handle this audio format? Also is there a media player I could buy that could handle it, as I should have a spare device to play these files in the event my LG Blu-Ray player were to conk out? Thanks in advance for any advice concerning this matter.

[KarMa]

HE-AAC(LC) is designed so that if it is not supported by the device, that the LC part can still be decoded and just ignoring the HE part(assuming it supports base level AAC-LC). This will give worse quality by cutting out any frequencies above ~10khz but will be playable. Does your device even support basic AAC-LC?

I remember doing something like this a decade ago. Encoding a bunch of my music to HE-AAC and was always puzzled why it sounded worse on my digital walkman, than on my computer. I found the walkman could only play AAC-LC and was not decoding the HE part.

[Tom Saurus]

KarMa: Thank you for your response. Here are the specs for some LC audio the LG Blu Ray will play:

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 42mn 5s
Bit rate mode : Variable
Bit rate : 80.0 Kbps
Maximum bit rate : 800 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Compression mode : Lossy
Delay relative to video : -2s 2ms
Stream size : 24.1 MiB (15%)

Here are the specs for the LC it won't play:

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AAC / LC
Codec ID : 40
Duration : 53mn 17s
Duration_LastFrame : -39ms
Bit rate mode : Variable
Bit rate : 80.0 Kbps
Maximum bit rate : 800 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz / 24.0 KHz
Compression mode : Lossy
Stream size : 30.5 MiB (12%)

I haven't tested this one yet:

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AACv2 / HE-AAC / LC
Codec ID : 40
Duration : 57mn 6s
Duration_LastFrame : -15ms
Bit rate mode : Variable
Bit rate : 80.0 Kbps
Maximum bit rate : 800 Kbps
Channel(s) : 2 channels / 2 channels / 2 channels
Channel positions : Front: L R / Front: L R / Front: L R
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz
Compression mode : Lossy
Stream size : 32.7 MiB (15%)

I remember hooking the LG Blu Ray player up to the network cable one day and checking out YouTube and it asked me if I wanted to update the firmware and I decided not to as it works so well with the exception of this type of audio not being supported. I also thought perhaps the firmware might take away some function that it currently has.

[videobruger]

If I re-encode the entire mp4 with both the video and the aud

How about an encoder that can "copy" the video and only reencode the audio like XmediRecode, MediaCoder, Video to Video ...

[Tom Saurus]

videobruger: I am certainly willing to give it a try. I can drop the mp4 into the video to video converter and select direct stream copy but it doesn't give me an option of re-encoding the audio. I can select to convert the file instead of direct stream copy to mp4/AVC but that doesn't give me an option of not re-encoding the video along with the audio. Thank you for your suggestion.

If someone can point me to a guide to do this process. What I did before was demux and select the audio and convert and then remuxing the converted video with the audio but then I ended up with out of sync video and audio. Thanks in advance for any additional information.

[Tom Saurus]

My LG Blu Ray player is the LG-BP325 and I like it because it plays .divx files as well and I wouldn't want to lose that functionality.

[videobruger]

I can select to convert the file instead of direct stream copy to mp4/AVC but that doesn't give me an option of not re-encoding the video along with the audio

Like this

[Tom Saurus]

videobruger: Thank you and I did a bit of experimenting and the mp4 file can be processed but one has to be wary of the video bit rate. I have put in the video bit rate of the original file and it turns out around the same file size. However I must be doing something wrong as the video specs don't match up when I look at them with media info. The original file specs:

Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 202 MiB
Duration : 52mn 6s
Overall bit rate mode : Variable
Overall bit rate : 543 Kbps
Writing application : Lavf56.4.101

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 5 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 52mn 5s
Bit rate : 458 Kbps
Width : 640 pixels
Height : 360 pixels
Display aspect ratio : 16:9
Original display aspect ratio : 16:9
Frame rate mode : Variable
Frame rate : 23.976 fps
Minimum frame rate : 12.500 fps
Maximum frame rate : 25.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.083
Stream size : 171 MiB (84%)
Writing library : x264 core 142 r2479 dd79a61
Encoding settings : cabac=1 / ref=5 / deblock=1:0:0 / analyse=0x3:0x113 / me=umh / subme=8 / 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=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=crf / mbtree=1 / crf=22.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / vbv_maxrate=800 / vbv_bufsize=1600 / crf_max=0.0 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AAC / LC
Codec ID : 40
Duration : 52mn 6s
Duration_LastFrame : -25ms
Bit rate mode : Variable
Bit rate : 80.0 Kbps
Maximum bit rate : 800 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz / 24.0 KHz
Compression mode : Lossy
Stream size : 29.8 MiB (15%)


The new file specs:

Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 201 MiB
Duration : 52mn 6s
Overall bit rate : 539 Kbps
Writing application : Lavf54.63.104

Video
ID : 1
Format : MPEG-4 Visual
Format profile : Simple@L1
Format settings, BVOP : No
Format settings, QPel : No
Format settings, GMC : No warppoints
Format settings, Matrix : Default (H.263)
Codec ID : 20
Duration : 52mn 6s
Bit rate mode : Variable
Bit rate : 458 Kbps
Width : 640 pixels
Height : 360 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.083
Stream size : 169 MiB (84%)
Writing library : Lavc54.92.100

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 52mn 6s
Bit rate mode : Constant
Bit rate : 81.3 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Compression mode : Lossy
Stream size : 30.3 MiB (15%)

There are changes in the video. But I could be doing something wrong. I have to master this though. I may have input the bit rate for each file as it varies. I am fairly certain the original files were converted using a "constant quality" setting so the video bit rate for each individual file is different because it adapts to such things as how much action is happening in a video and such. These are captured streaming video files so I rely on whatever way they were converted in the first place. Idealey I want the exact same video specs as the original files with no need to input the exact video bit rates each time so that I can batch convert with the newly encoded audio specs. Perhaps it is not possible. Thanks in advance for any advice on this matter.

[Tom Saurus]

I dropped the original file into VideoReDo and chose save as then selected "yes" when it asked if I wanted to remux the file. Then I chose edit output profile. Under video I chose "same as source". Output mode is set as intelligent recode. I went down to audio and selected it to re-encode to aac. Well it turned out a lot closer to my original specs. Here is the MediaInfo specs for the original file:

Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 217 MiB
Duration : 57mn 6s
Overall bit rate mode : Variable
Overall bit rate : 532 Kbps
Writing application : Lavf56.4.101

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 5 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 57mn 6s
Bit rate : 447 Kbps
Width : 640 pixels
Height : 360 pixels
Display aspect ratio : 16:9
Original display aspect ratio : 16:9
Frame rate mode : Variable
Frame rate : 23.976 fps
Minimum frame rate : 12.500 fps
Maximum frame rate : 25.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.081
Stream size : 183 MiB (84%)
Writing library : x264 core 142 r2479 dd79a61
Encoding settings : cabac=1 / ref=5 / deblock=1:0:0 / analyse=0x3:0x113 / me=umh / subme=8 / 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=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=crf / mbtree=1 / crf=22.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / vbv_maxrate=800 / vbv_bufsize=1600 / crf_max=0.0 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AACv2 / HE-AAC / LC
Codec ID : 40
Duration : 57mn 6s
Duration_LastFrame : -15ms
Bit rate mode : Variable
Bit rate : 80.0 Kbps
Maximum bit rate : 800 Kbps
Channel(s) : 2 channels / 2 channels / 2 channels
Channel positions : Front: L R / Front: L R / Front: L R
Sampling rate : 48.0 KHz / 48.0 KHz / 24.0 KHz
Compression mode : Lossy
Stream size : 32.7 MiB (15%)

The MediaInfo specs for the outputted file from VideoReDo:

Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 223 MiB
Duration : 57mn 6s
Overall bit rate : 547 Kbps
Writing application : Lavf53.31.100

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 5 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 57mn 6s
Bit rate : 449 Kbps
Width : 640 pixels
Height : 360 pixels
Display aspect ratio : 16:9
Original display aspect ratio : 16:9
Frame rate mode : Variable
Frame rate : 23.976 fps
Minimum frame rate : 23.952 fps
Maximum frame rate : 24.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.081
Stream size : 183 MiB (82%)

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 57mn 6s
Duration_LastFrame : -32ms
Bit rate mode : Constant
Bit rate : 96.0 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 32.0 KHz
Compression mode : Lossy
Stream size : 38.5 MiB (17%)

It outputted quite quickly and I saved it as a new profile. I would imagine I can run each file through one at a time and same them to be batch outputted when I am done. I suppose the video is re-encoded somewhat though as the video bit rate changed from 447 to 449.

[Tom Saurus]

I have decided that VideoReDo is the best solution for this kind of thing. There is obviously a slight recode of the video because the bit rate changes a bit for that but it is fairly quick. But it might be best to do each file individually once you have your profile figured out. I have found that you get the odd file when you manually add a file to the quenue for the batch mangager that stalls for whatever reason and it best you figure that out before hand as having to abort and go back in can be a pain and you could have been stalled for quite sometime before you checked back and that would be a waste of time and resources.