Timeline for Does repeatedly saving a video degrade its quality?
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
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| May 4, 2016 at 22:13 | vote | accept | Jeff Caros | ||
| May 2, 2016 at 12:59 | comment | added | Jim Mack | @Mulvya Yes, that's why I said "depending on the encoder and settings". Presumably when saving from an NLE for later reopening you're not using a CRF, and you're saving with reasonable quality. Your point is valid, but in practical terms you have to make a lot of passes, and bad decisions, before you actually see any degradation beyond the first loss. | |
| May 2, 2016 at 11:56 | comment | added | Gyan | "If you save again using the same settings, there's no information to lose in the areas that have already lost it." --> Empirically, it doesn't work out this way. If a video is re-encoded at CRF 18 using x264 for 5 cycles, the 1st generation shows a SSIM score of ~99% and the 5th gen, ~98.5%. But for a CRF 23 cycle, 1st gen is ~98.7% and 5th gen is ~97.5%. So more aggressive the compression, faster the drop-off for subsequent encodes. | |
| May 2, 2016 at 11:11 | history | answered | Jim Mack | CC BY-SA 3.0 |