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ADTS not read

Started by DevoCut, May 21, 2018, 08:46:37 PM

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DevoCut

So I've been playing around with this for a while,

(sample file can be found here: https://drive.google.com/open?id=1UIJhy0v6875lSbSMM-5AHaqpppBIQNfh )

VLC detects it as ADTS codec for audio, both 2.7 and 2.6 doesn't seem to detect any audio tracks. I can get the last version of 2.5 to read it just fine (I haven't tested other versions of 2.5) But the 2.5 seems to have trouble with timecode?, and ends up treating the file at 2x speed.

Curious if there was something I was doing wrong.

eumagga0x2a

Thank you for the sample. With TS_MAX_PACKET_SCAN at avidemux_plugins/ADM_demuxers/MpegTS/ADM_tsBruteForce.cpp:29 bumped to 3000, Avidemux detects audio track successfully. However, audio starts ~3 seconds after video, which probably isn't right. It is correctable with a large negative shift value.

DevoCut

Quote from: eumagga0x2a on May 21, 2018, 09:43:59 PM
Thank you for the sample. With TS_MAX_PACKET_SCAN at avidemux_plugins/ADM_demuxers/MpegTS/ADM_tsBruteForce.cpp:29 bumped to 3000, Avidemux detects audio track successfully. However, audio starts ~3 seconds after video, which probably isn't right. It is correctable with a large negative shift value.

I'm confused, so is the fact that the audio is delayed by 3 seconds is why the UI shows no audio tracks and can't output any audio?

DevoCut

This is another file I've been trying to get audio to work with, The first file had working audio in verision 2.5 so I thought that would be an easier fix.

https://drive.google.com/file/d/19vwSSkRj5eR_otyqRa7gdRyItnYUx8tz/view?usp=sharing

VLC reports this audio codec as 302M Audio, Haven't heard of that before, but it came out of an Evertz dreamcatcher so my guess it's an older mpeg 2 era codec. VLC and any other media player can play this file fine, but no version of Avidemux seems to be able to see the audio tracks.

eumagga0x2a

Quote from: DevoCut on May 21, 2018, 11:20:35 PM
I'm confused, so is the fact that the audio is delayed by 3 seconds is why the UI shows no audio tracks and can't output any audio?

Avidemux has to brute-force the stream looking for usable streams. It looks like the audio stream starts too late in the file. Cutting away a small portion of the stream (I tried it with 512K) allows Avidemux to detect the audio stream without any modifications of the code.

DevoCut

Ok that makes more sense, I'm trying to develop a workflow though so this isn't really gonna help me save time if I have to hex edit each file anyway. I'll see if I can find another piece of software to re wrap it. Or find a way to get 2.5 to understand the file speed properly.

eumagga0x2a

Just

ffmpeg -i your_file.ts -c copy output_file.ts

or use dd (there should be a build for Windows somewhere).