From: Tuukka Toivonen [mailto:tuukkat@ee.oulu.fi]
Smaller q is better image quality. Since almost all quantization parameters are at 2 and 3, the quality should be very good. I know, but read on and you'll see the reason why I ask.
Does this mean I should decrease the resolution? If I understand other
I suspect it would not help. You could try encoding with lower resolution and the same bitrate and see which one looks better, if you have time. Otherwise, don't bother, it's probably good already.
Dont think I'll bother. And like you say, it's already good. Very good. I was just puzzled by the fact that the encoding-tips.txt states "... e.g. the lowest quantizer (vqmin=2) gets used for > 95% of the frames then you can safely increase your picture size." Implicitly, this means I should scale down. Isn't >95% q=2 a rather extreme measure? When should I *stop* increasing the picture size then? At >50% q=2? Would the use of q=2 increase very rapidly as the movie W:H decreases just a little? Again, I can encode to test, but if some of you know the answer, I can use my time for something else. I also encoded the same movie with -xvidencopts max_key_interval=125:bitrate=1802:me_quality=6:4mv (with passes 1/2) for comparison, and I honestly cannot see the difference... havent studied it thoroughly though, just browsed through briefly, looking at dark areas, smoke/clouds, water, edges with high color gradients and such... what should I be looking for? Maybe the bitrate is too high for any differences to be easily noticed? I used the same scaler in both encodings (-sws 2). If I have time to spare some day, I'll extract some frames and arm myself with a microscope and some image analyzing tools... :p~
trell and vpass for two/three pass encoding would be very good. Also -vf hqdn3d, if it is TV source (probably not good if it's from DVD). It's a DVD encoding. And always use 3pass (audio + vpass=1/2), I just didn't paste it in... ;)
How useful is trell for DVD encodings? Should be less noise there than from a TV/VCR source? How does digital TV broadcasting fit in here? I also considered using mbd=1, or is that the default when using vhq? I mean if there's a difference between the "vhq" turned on by mbd=1 and the vhq parameter, what is it? And if not, do they work well together? HR