Manao
15th December 2003, 19:50
I open a new thread for users to post their comments on these features : in which case did they give a good result, in which other case they were disappointing.
I hope than, this way, we'll be able to get an idea of when one should use such or such features.
For my part, here are my results.
I made a bench test on 'The Hours' ( PAL, 16/9, 1h50, and a kind of film effect ), encoding the whole movie, keeping the first and second passes, with different settings enabled.
But, firstly, the avs I used, which is pretty simple :MPEG2Source("R:\hours.d2v",cpu2="oooooo")
crop(2,12,-0,-10)
LanczosResize(640,352)There is no denoising, because I wanted to retain the grain of the movie. Lanczos, of course, because I want the picture to be sharp, and because the first pass isn't too high for a 1-CD ripp.
The common settings are :
- ME 6, VHQ 4, Chroma motion on, Frame drop ratio 0, Max I-Frame interval 300
- Cartoon mode off, Reduce resolution off, Interlaced off
- B-Frames 2, 1.5, 0.75, 0
- Unrestricted profile
- Chroma optimizer off, No capped quants
- Default second pass's settings
- Second pass size : 579 400 Kb
For each encodes, I made a SSIM test and a visual one. The SSIM value is calculated with lumimasking, and without including the credit in the calculation. I used the following script :source = MPEG2Source("R:\hours.d2v",cpu2="oooooo"). \
trim(0,158000).crop(2,12,-0,-10).lanczosresize(640,352)
result = AVISource("R:\hours.avi").trim(3,158003)
ssimvalue = SSIM(source,result,"R:\hours.csv","R:\hours.txt",lumimask = true)
return ssimvalueHere are the table of the sizes / SSIM values obtained :
Options | Fst Pass | Snd Pass
--------------------------------+---------+----------+--------------
| Size | SSIM | SSIM
| | |
H263 - Treillis - AQ - GMC | 1151 | ~80 (1) | 74.56 (*)
H263 - AQ - GMC | 1209 | ~80 (1) | 74.50 (*)
HVSGOOD - Treillis - AQ - GMC | 1019 | 78.37 | 74.49 (*)
HVSGOOD - AQ - GMC | 1008 | 78.44 | 74.54 (*)
HVSGOOD - AQ | 997 | 78.45 | 74.32
HVSGOOD | 1027 | 78.73 | 74.57
HVSGOOD - QPel - Treillis | 1039 | 77.51 | 74.22
HVSGOOD - QPel | 1026 | 77.58 | 74.30
HVSGOOD - QPel - AQ | 989 | 77.32 | 74.07
HVSGOOD - QPel - GMC - Treillis | 1039 | 77.69 | 74.42
H263 - QPel - Treillis | 1087 | 79.49 | 74.79
HVSGOOD - QPel - BF(2,1,1) | 1027 | 77.58 | 74.00
HVSGOOD - QPel - BF(1,1.5,0.75) | 1091 | 78.06 | 74.17
HVSGOOD - QPel - No BF | 1405 | 79.64 | 73.61
MPEG - Qpel | 1201 | 78.42 | 74.30
HVSBEST - QPel | 1179 | 78.28 | 74.22(1) : I lost the .txt containing the SSIM value, but I recall it being higher than 80
(*) : It was slightly oversized ( 3-5 Mb ), but results are still valid.
And now, the visual impression, which is imho the most important, and which tends to disapprove SSIM results.
Concerning the matrix quant : HVSGOOD gives better results, visually, than H263, even at quant 2 ( and even if the SSIM is lower by 1.5 ). The HVS matrix retains noise better than H263. On this movie, ringing / mosquito noise at quant 2 are not perceptible. In two pass mode, you can see it, but it is still light, and visible both with H263 and HVSGOOD. I'm currently making a test with H263 and QPel to see if it improves the results for H263.
Concerning Adaptive Quantization, GMC and Treillis : I could not spot visual differences. Adaptive quantization reduces first pass size by roughly 30 Mb, but I can't spot on my computer its effects. Nor can I say that in two pass mode, the overall quality is better. The effect of GMC seems strange quantitatively speaking ( it increases the first pass size, and lowers ( by 0.01 ) the SSIM. I'm currently checking if I didn't make a mistake here ), but no effects visually speaking. Finally Treillis will also have to be probed more deeply.
Finally, QPel. I already tried it on 'The beauty and the Beast', and I didn't like its effect. Well, this time, it's the contrary. What impressives results it gave me. I must confess I tried it only because I made a mistake configuring the codec, but I'm glad having made this one. It seems to like noise ( or grain, call it as you want ).
I'll try to take screenshots, but it takes time that I won't have until friday. I'm currently testing (H263 + QPel + Treillis) and (HVSGOOD + QPel + GMC), and I'll try different B-Frames settings soon. I'll add SSIM values / impression on this post.
But I'm eager to hear your experiences with these settings, and with B-Frames.
Edited : I added some results, and more will come soon, concerning b-frames settings this time. Visually speaking, QPel helped a lot for H263, but it still doesn't reach the quality of the HVS_GOOD matrix. Now testing b-frames ( 1,1.5,0.75 and 2,1,1, against the defaults : 2,1.5,0.75, with hvs_good and qpel enabled in each case
Edited 2 : Added different b-frames settings, now testing other matrices ( HVSBEST, HVSBETTER, MPEG ), with defaults b-frames and QPel, and HVSGOOD without b-frames.
Edited 3 : I compared the clip encoded with and without b-frames. They really bring quality. They do not blur the picture, but they give instead a less noisy picture ( on walls especially ). The only advantage of not using b-frames was slightly more stable walls. But else picture's quality was definitely better with b-frames on. The three different settings seem pretty close quality wise, I'll make further investigation. Screenshots are due to arrive during the week-end. I added some numbers, and I forgot to mention the aimed size, which was 579 400 Kb.
Edited 4: I bean to put screenshots. For the moment, two series illustrating the effects of the matrix ( all are made with QPel and b-frames ), and of QPel ( on H263 and HVS_GOOD ). Have a look here (http://www.geocities.com/manao47/index.htm). I asked a friend which pictures he prefered, she answered me twice the H263 - QPel. It's different from what I think ( I prefer HVSBest - Qpel, and HVSGood - QPel ), so you'll have to check to choose which one you prefer.
I hope than, this way, we'll be able to get an idea of when one should use such or such features.
For my part, here are my results.
I made a bench test on 'The Hours' ( PAL, 16/9, 1h50, and a kind of film effect ), encoding the whole movie, keeping the first and second passes, with different settings enabled.
But, firstly, the avs I used, which is pretty simple :MPEG2Source("R:\hours.d2v",cpu2="oooooo")
crop(2,12,-0,-10)
LanczosResize(640,352)There is no denoising, because I wanted to retain the grain of the movie. Lanczos, of course, because I want the picture to be sharp, and because the first pass isn't too high for a 1-CD ripp.
The common settings are :
- ME 6, VHQ 4, Chroma motion on, Frame drop ratio 0, Max I-Frame interval 300
- Cartoon mode off, Reduce resolution off, Interlaced off
- B-Frames 2, 1.5, 0.75, 0
- Unrestricted profile
- Chroma optimizer off, No capped quants
- Default second pass's settings
- Second pass size : 579 400 Kb
For each encodes, I made a SSIM test and a visual one. The SSIM value is calculated with lumimasking, and without including the credit in the calculation. I used the following script :source = MPEG2Source("R:\hours.d2v",cpu2="oooooo"). \
trim(0,158000).crop(2,12,-0,-10).lanczosresize(640,352)
result = AVISource("R:\hours.avi").trim(3,158003)
ssimvalue = SSIM(source,result,"R:\hours.csv","R:\hours.txt",lumimask = true)
return ssimvalueHere are the table of the sizes / SSIM values obtained :
Options | Fst Pass | Snd Pass
--------------------------------+---------+----------+--------------
| Size | SSIM | SSIM
| | |
H263 - Treillis - AQ - GMC | 1151 | ~80 (1) | 74.56 (*)
H263 - AQ - GMC | 1209 | ~80 (1) | 74.50 (*)
HVSGOOD - Treillis - AQ - GMC | 1019 | 78.37 | 74.49 (*)
HVSGOOD - AQ - GMC | 1008 | 78.44 | 74.54 (*)
HVSGOOD - AQ | 997 | 78.45 | 74.32
HVSGOOD | 1027 | 78.73 | 74.57
HVSGOOD - QPel - Treillis | 1039 | 77.51 | 74.22
HVSGOOD - QPel | 1026 | 77.58 | 74.30
HVSGOOD - QPel - AQ | 989 | 77.32 | 74.07
HVSGOOD - QPel - GMC - Treillis | 1039 | 77.69 | 74.42
H263 - QPel - Treillis | 1087 | 79.49 | 74.79
HVSGOOD - QPel - BF(2,1,1) | 1027 | 77.58 | 74.00
HVSGOOD - QPel - BF(1,1.5,0.75) | 1091 | 78.06 | 74.17
HVSGOOD - QPel - No BF | 1405 | 79.64 | 73.61
MPEG - Qpel | 1201 | 78.42 | 74.30
HVSBEST - QPel | 1179 | 78.28 | 74.22(1) : I lost the .txt containing the SSIM value, but I recall it being higher than 80
(*) : It was slightly oversized ( 3-5 Mb ), but results are still valid.
And now, the visual impression, which is imho the most important, and which tends to disapprove SSIM results.
Concerning the matrix quant : HVSGOOD gives better results, visually, than H263, even at quant 2 ( and even if the SSIM is lower by 1.5 ). The HVS matrix retains noise better than H263. On this movie, ringing / mosquito noise at quant 2 are not perceptible. In two pass mode, you can see it, but it is still light, and visible both with H263 and HVSGOOD. I'm currently making a test with H263 and QPel to see if it improves the results for H263.
Concerning Adaptive Quantization, GMC and Treillis : I could not spot visual differences. Adaptive quantization reduces first pass size by roughly 30 Mb, but I can't spot on my computer its effects. Nor can I say that in two pass mode, the overall quality is better. The effect of GMC seems strange quantitatively speaking ( it increases the first pass size, and lowers ( by 0.01 ) the SSIM. I'm currently checking if I didn't make a mistake here ), but no effects visually speaking. Finally Treillis will also have to be probed more deeply.
Finally, QPel. I already tried it on 'The beauty and the Beast', and I didn't like its effect. Well, this time, it's the contrary. What impressives results it gave me. I must confess I tried it only because I made a mistake configuring the codec, but I'm glad having made this one. It seems to like noise ( or grain, call it as you want ).
I'll try to take screenshots, but it takes time that I won't have until friday. I'm currently testing (H263 + QPel + Treillis) and (HVSGOOD + QPel + GMC), and I'll try different B-Frames settings soon. I'll add SSIM values / impression on this post.
But I'm eager to hear your experiences with these settings, and with B-Frames.
Edited : I added some results, and more will come soon, concerning b-frames settings this time. Visually speaking, QPel helped a lot for H263, but it still doesn't reach the quality of the HVS_GOOD matrix. Now testing b-frames ( 1,1.5,0.75 and 2,1,1, against the defaults : 2,1.5,0.75, with hvs_good and qpel enabled in each case
Edited 2 : Added different b-frames settings, now testing other matrices ( HVSBEST, HVSBETTER, MPEG ), with defaults b-frames and QPel, and HVSGOOD without b-frames.
Edited 3 : I compared the clip encoded with and without b-frames. They really bring quality. They do not blur the picture, but they give instead a less noisy picture ( on walls especially ). The only advantage of not using b-frames was slightly more stable walls. But else picture's quality was definitely better with b-frames on. The three different settings seem pretty close quality wise, I'll make further investigation. Screenshots are due to arrive during the week-end. I added some numbers, and I forgot to mention the aimed size, which was 579 400 Kb.
Edited 4: I bean to put screenshots. For the moment, two series illustrating the effects of the matrix ( all are made with QPel and b-frames ), and of QPel ( on H263 and HVS_GOOD ). Have a look here (http://www.geocities.com/manao47/index.htm). I asked a friend which pictures he prefered, she answered me twice the H263 - QPel. It's different from what I think ( I prefer HVSBest - Qpel, and HVSGood - QPel ), so you'll have to check to choose which one you prefer.