Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-26 Thread Simon Brown
> > > > Ok, I've cheated somewhat, and taken my (much older) ffmpeg and > editted isom.c so that rather than substituting 0x40 for AV_CODEC_ID_AAC it > now substitutes 0x67 instead. If I look at the resulting output file with > mp4info and the output of FFmpeg itself they both show that it's MP4 A

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-26 Thread Simon Brown
> > > > So it seems to be a matter of TS demuxing passing along the codec > extradata correctly. > > Regards, > Tobias > > Thank you both for your replies. Ok, I've cheated somewhat, and taken my (much older) ffmpeg and editted isom.c so that rather than substituting 0x40 for AV_CODEC_ID_AAC it no

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-25 Thread Tobias Rapp
On 24.05.2021 22:26, Moritz Barsnick wrote: On Wed, May 19, 2021 at 12:17:38 +0200, Tobias Rapp wrote: Looks like the data that should be found in the "esds" atom is missing or incomplete when using -c:a copy. See this link for details on how AAC profile information is stored in MP4: https://st

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-24 Thread Moritz Barsnick
On Mon, May 24, 2021 at 22:26:03 +0200, Moritz Barsnick wrote: > MPEG-TS and demuxing isn't the problem. If you look at the ffmpeg > output in the original e-mail from decoding the file, it correctly > identifies the codec as "aac (LC)". The issue is the encoding to MP4. On the other hand, when I

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-24 Thread Moritz Barsnick
On Wed, May 19, 2021 at 12:17:38 +0200, Tobias Rapp wrote: > Looks like the data that should be found in the "esds" atom is missing or > incomplete when using -c:a copy. See this link for details on how AAC > profile information is stored in MP4: > > https://stackoverflow.com/questions/3987850/mp4-

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-19 Thread Tobias Rapp
On 14.05.2021 15:31, Simon Brown wrote: [...] For although there it says aac (LC) if I run mp4info on the resultant file I get this: [...] Track 2: flags:3 ENABLED IN-MOVIE id: 2 type: Audio duration: 0 ms language: und media: sample count: 0

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-18 Thread Moritz Barsnick
On Mon, May 17, 2021 at 23:34:45 +0100, Simon Brown wrote: > Thank you for your reply. If it is the bitstream filter could you point me > to the relevant source file that is responsible for this filter? Sure, it's here: https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/aac_adtstoasc_bsf.c

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-17 Thread Simon Brown
> > > On Fri, May 14, 2021 at 14:31:42 +0100, Simon Brown wrote: > > Hi, > > I have a mpeg2 transport stream with video as H264 and audio as AAC LC. > If > > I use the following command to convert it to fragmented MP4 by just > copying > > the encoded data, then the result is now AAC, and not AAC L

Re: [FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-17 Thread Moritz Barsnick
On Fri, May 14, 2021 at 14:31:42 +0100, Simon Brown wrote: > Hi, > I have a mpeg2 transport stream with video as H264 and audio as AAC LC. If > I use the following command to convert it to fragmented MP4 by just copying > the encoded data, then the result is now AAC, and not AAC LC. If instead I

[FFmpeg-user] Preserving AAC LC status when converting to fragmented MP4

2021-05-14 Thread Simon Brown
Hi, I have a mpeg2 transport stream with video as H264 and audio as AAC LC. If I use the following command to convert it to fragmented MP4 by just copying the encoded data, then the result is now AAC, and not AAC LC. If instead I re-encode with AAC asking for profile:a aac_low then I get AAC LC.