Doom9's Forum - View Single Post - Convert DTS to Dolby and any Lossless to Apple Lossless [BluRay]

FLX90 · 3rd January 2019, 08:40

Solved #4, #4 and #5.

#4a & #5:
Warning had something to do with variable frame rate and timecodes.
Timecodes get lost during extract h264 from mkv.
Avoid this problem by directly converting from one container to another:
ffmpeg -i german_dd_to_alac__english_dtshdma_to_alac.mkv -map 0:0 -c copy temp.m4v

Choppy video playback mentioned here had also something to do with converting VFR to CFR (MPC-HC handled that anyway, ATV doesn't).

With this, probesize error also disappeared.

#4b:
Solved this by specifying audio codec -c:a alac.
Don't know why but worked.

Another question:
Like I said I'll convert everything to ALAC.
But I don't know which bit depth for the lossy audio streams.
To lose as less information as possible I do the following:
Convert lossy audio to 24 bit flac.
Check if last 8 bits are used.
If so I convert to 24 bit ALAC.
If not I convert to 16 bit ALAC.

Is this the best way to do?

I asked in another forum and they said I should convert to 16 bit and don't waste much thought on the 8 bits.
But couldn't explain me why.
My thinking was that 48 dB possible difference in dynamic range (144 db <-> 96 dB) is essential to preserve, especially for movie audio.

What would you say?

3rd January 2019, 08:40	#14 \| Link
FLX90 Registered User Join Date: Nov 2018 Posts: 34	Solved #4, #4 and #5. #4a & #5: Warning had something to do with variable frame rate and timecodes. Timecodes get lost during extract h264 from mkv. Avoid this problem by directly converting from one container to another: ffmpeg -i german_dd_to_alac__english_dtshdma_to_alac.mkv -map 0:0 -c copy temp.m4v Choppy video playback mentioned here had also something to do with converting VFR to CFR (MPC-HC handled that anyway, ATV doesn't). With this, probesize error also disappeared. #4b: Solved this by specifying audio codec -c:a alac. Don't know why but worked. Another question: Like I said I'll convert everything to ALAC. But I don't know which bit depth for the lossy audio streams. To lose as less information as possible I do the following: Convert lossy audio to 24 bit flac. Check if last 8 bits are used. If so I convert to 24 bit ALAC. If not I convert to 16 bit ALAC. Is this the best way to do? I asked in another forum and they said I should convert to 16 bit and don't waste much thought on the 8 bits. But couldn't explain me why. My thinking was that 48 dB possible difference in dynamic range (144 db <-> 96 dB) is essential to preserve, especially for movie audio. What would you say?