以下是相关的介绍：
The Helix Producer 9.2 June 4th build includes an EHQ mode that I am quite happy with [hopefully everything else is okay, because I have only been testing the codec, and have not tested that exact Producer build too much].
For certain content a quality improvement corresponding to a 30% bitrate reduction can be seen, and this is with a fully backwards compatible bitstream. On average though, and for very high bitrate content, it will be less, but for my current test encodings I can reduce the number of bits/pixel quite significantly, and have the result still look very pleasing.
It will be very interesting to get some feedback. Remember though, every improvement is incremental, and it takes some time to adjust to the new mode. For instance, if you previously used such a high bitrate relative to resolution, that no compression artifacts could be seen, using the same bitrate now, you will still see no visual degradation. The improvement then would have been that you could have gotten away with a lower bitrate and still have seen no problems. I know you will ask if it can be made faster, and the answer is that every CPU cycle is spent trying to find more optimal compression parameters, and every CPU intensive function is fully MMX/SSE/SSE2 optimized. I would rather have my computer's 2.4 GHz P4 do that instead of searching for aliens in its free time
Will the improvement be worth the slower encoding speed? Well, certainly for me it will, but if your CPU is on the slow side, it may be too much. I have used it enough now to see the improved visual quality. I can now lower the bitrate more without seeing "stuff going on" both in the background and around edges. Of course, being the implementor, it is not possible to get more biased, but I am very happy with the result.
As you may know, PSNR measurements are the most commonly used indication of compression efficiency for video codecs. Compared with for instance VSS H.264 codec in its best quality mode, RV9-EHQ has higher compression efficiency, and encodes 25X faster. I may post a couple of these PSNR charts.
Enabling RV9-EHQ
Audience/job file:
Include the following in the section of the audience:
code:--------------------------------------------------------------------------------
80
16000
--------------------------------------------------------------------------------
encoderComplexity sets the EHQ level:
65 = Default : improved efficiency for high action
70 = High : same as 65 + better mode decisions, better representation of high motion
80 = Extra High: same as 70 + best possible mode decisions, very high accuracy motion representation
(50 = Fast : not recommended, use only for Live capture encoding)
as you can see, there is some improvement even for the default mode.
The customPacketSize parameter increases compression efficiency for high action. Note that streams compressed with the customPacketSize parameter set to 16000 are not recommended for Internet streaming. This parameter will be default for VBR over a certain bitrate, but is needed for now.
Encoding times:
(65) same encoding time as before
(70) will take about 2X - 2.5X encoding time compared to default
(80) about 3X - 4X default
Registry over-rides
--->8---
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\RealNetworks\RV9]
"encoderComplexity"=dword:00000050
"customPacketSize"=dword:00003e80
--->8---
[copy and paste this to a new file, save as rv9enc.reg, double-click to enter in registry. Please remember that you have these these keys, otherwise the audience file settings will have no effect. These keys may change in the future]
These settings can be used after replacing the encoder DLL in the GUI Helix Producer, and any other tool which does not have the EHQ setting. Note that the encoder DLL needs to be replaced in all cases...
IMPORTANT: These values are in HEX so 0x50 = 80 decimal, and 0x3e80 = 16000 decimal. Remember to click the Decimal checkbox when entering new values in the registry editor.
