On 2/23/2014 10:22 PM, Tom Vaughan wrote: > Does the MKV contain video that was ripped straight from the Blu-ray Disc? > The video in the MKV is only 14 Mbps... I would have expected a higher bit > rate (and more detail) if this was not re-encoded. It would be best to > start with the highest quality source possible.
This is a red herring argument. The vast, *vast* majority of actual use cases will be recompressing existing content. Also, 14 mbps is hardly low. I would almost argue it's not interesting to compress from ridiculously high quality or lossless sources, except to test pure improvement changes (i.e. devs). > Notice that prova.h264 is twice the size (12 MB) of prova.h265 (6 MB). This > explains some of the difference in quality. It's hard to hit a bit rate > target with such a short clip. You may need to use CRF, experimenting with > different values until you get close. I think that your test method is > valid, and the results are very interesting, but you have to make sure that > you end up with identical bit rates. Answered by Niccolò elsewhere. > To be fair, we want to compare encoded frames to the original incoming > frames. We don't want to consider "more compression artifacts" to be "more > detail". So you completely discount the notion of psychovisual optimization... ? > There are definitely some areas where your x264 encode preserved > more detail, such as in the waves on the water, or the green areas in the > landscape. I noticed that even at half the bit rate, the x265 encode > provides much more accurate edge definition of objects in motion and far > lower noise than the x264 encode. Notice how you can see the individual > feathers in the close-up shots of the birds flying. As noted in Niccolò's email, it's not half the bitrate. I must say, as a viewer, similar complexity > blur, always. You see this sort of thing almost all the time in PSNR-optimized ratecontrol, and it's sad. [...] - Derek _______________________________________________ x265-devel mailing list [email protected] https://mailman.videolan.org/listinfo/x265-devel
