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+--- Thread: [INFO] Constant Quantizer Lossless Option (/thread-3580.html)
Constant Quantizer Lossless Option - wdsongama - 14.02.2024
What is the lossless option for since what we do is a lossy proccess? Does it make any difference if I specify the bitrate the same as my source file?
RE: Constant Quantizer Lossless Option - Selur - 14.02.2024
Hope this helps, a bit:
The following happens during reencoding:
1. the source gets decoded (so a raw video stream is created)
2. the source video is fed to an encoder which then compresses this data
when you choose lossless encoding all the data in the decompressed source will be kept.
If not, data will be lost. Depending on the compression level more or less data or the original will be lost and altered.
This alteration on one hand allows lower datarate, but also created compression artifacts&co.
So if you now take a compressed source and decode it again, this altered data is the new original data.
Compressing this data with the previous data rate will again cause data loss,..
see: https://en.wikipedia.org/wiki/Generation_loss
=> unless the data rate you chose is the same data rate that the is needed for a lossless reconstruction of the input data you will alter the data.
Cu Selur
Ps.: I'll move this thread to the 'A/V Talk' section, since this has nothing to do with Hybrid.