Dear VNC developer.
Introduction of "ZYWRLE":Enhanced VNC codec for Motion picture 1. Introduction The lossy codec based on Wavelet transform is frequently used in compression of natural image, motion picture and audio stream. But it isn't almost used in Remote Desktop protocol like VNC because classical lossless run-length codec like ZRLE has high performance in peculiar image which has big mono color region like desktop image. The lack of lossy codec cause low performance of motion picture in VNC. We introduce new codec "ZYWRLE(ZLib YUV Wavelet Run Length Encoding)" which applied wavelet transform partially and is based on ZRLE. In this new codec, network traffic reduced to 15%-50% traffic of ZRLE when we play motion picture. 2. Highlight of Evalution of ZYWRLE Result of ZYWRLE for motion picture +-------+-------------------+------------------+------------------+ |quality| Raw tile(Mbytes) | Total(Mbytes) |Raw tile|PSNR(RGB)| | | Out | Raw |rate | Comp.| Raw |rate| rate(%)| (dB) | +-------+------+------+-----+------+------+----+--------+---------+ | ZRLE |125.8 |125.8 |100 |117.1 |392.2 |29.8| 32.1 | INF. | | Hi | 53.85|167.58| 32.1| 52.10|370.96|14.0| 45.1 | 28.025 | | Mid | 31.83|264.05| 12.1| 20.56|378.50| 5.4| 69.7 | 23.980 | +-------+------+------+-----+------+------+----+--------+---------+ * Comp. rate of ZRLE(about 30%) goes to 15%(Hi-quality)/5%(Mid-quality)! 3. Reference Implementation(C source code/patch for VNC Servers) * Core Codec of ZYWRLE http://mobile.hitachi-system.co.jp/publications/ZYWRLE/zywrletemplate.c * Patch for [EMAIL PROTECTED] V1.0.2 http://mobile.hitachi-system.co.jp/publications/ZYWRLE/UltraVNC-102-ZYWRLE-diff.txt * Patch for LibVNCServer 0.8.2 http://mobile.hitachi-system.co.jp/publications/ZYWRLE/LibVNCServer-0.8.2-ZYWRLE-diff.txt I think that Any VNC server can be applied ZYWRLE easlilly using one of these patch. 4. License of ZYWRLE Though ZYWRLE is our intellectual property and was developed for our micro-VNC, We Hitachi Systems & Services, Ltd. decided make it open source. You can use it with no fee for commercial and/or non-commercial purpose. The above reference implementation are released under our BSD-like license. More detail, see top of zywrletemplate.c. 5. More detail See our ZYWRLE page(http://mobile.hitachi-system.co.jp/publications/ZYWRLE/) We are glad if your VNC server supports ZYWRLE. Thank you. --- Noriaki Yamazaki Administrator of micro-VNC Research & Developement center Hitachi Systems & Services, Ltd. _______________________________________________ VNC-List mailing list VNC-List@realvnc.com To remove yourself from the list visit: http://www.realvnc.com/mailman/listinfo/vnc-list