-高端Profile(High Profile,也叫FRExt)在主要Profile 的基础上增加了8x8 内部预测、自定义量化、无损视频编码和更多的YUV 格式(如4:4:4)。 hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
或许只有在将来才能知道哪些Profile 或哪些功能会成为DVDRIP 的主流,但是我猜想会是Main 或是High Profile,包含下面的一些功能:( 这里你可以不必看)hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
CAVLC/CABAC hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Loop/Deblocking Filter hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Variable Block Sizes/Macroblock Partitions (可变区块尺寸/ 微块分割)hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Multiple Reference Frames (多重参照帧) hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Weighted Prediction (权重预测) hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Rate Distortion Optimisation (RDO ,评价变化优化)hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
AVC profile的设置主要是针对兼容性的,一些特定的硬件播放器需要指定的profile编码才能被识别,具体的例子有PSP,iPOD视频等,他们都有自己指定的profile。PSP是main profile/level 3,其他可能会有兼容性问题,这点切记!!!要是这些profile已经把你搞糊涂了的话,AVC Level就更多了。level有十来个,每个profile都对应这些level。因此可以有更细致的分类。hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
要是只是准备在自己PC上播放的话,可以不去管这些实际的profile和level,因为pc的好处就是通杀,无所谓。hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
下面来完全对比一下Xvid和H.264,看看到底哪个更有前途 注意测试平台是PC,PSP由于有局限性,所以后面我会给出用MeGui压MP4格式AVC的方法hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
MPEG-4 Video 中包含有2个标准:ISO 14496-2 (Video)和ISO 14496-10 (Video),亦即通常说的 MPEG-4 ASP 和 MPEG-4 AVC。hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
现在来看一下2个不同 Profile 的 Codec 在编码质量上的差别!hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
我分别选了2个开源的Codec:XviD 和 x264进行简单测试hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
尝尝AVC/H.264给我们带来了什么!hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
考虑到动画比较能突出重点细节,且现在很多小孩喜欢看动画,所以先选一段hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
源为《ハウルの動く城》Chapter 17的动画hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
首先来看看视源的特性,使用XviD q2 的编码作为参考hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
编码参数设置,目标码流设置为 xvid q2 码流的一半,使用2-pass编码hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
xvid-1.2.cvs.2005.12.10hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
QUOTE:
VHQ4,Use VHQ for bframes too,BVOPs=2,ratio=1,offset=2,Max I-frame quantizer:2,Quarter Pixel,Global Motion CompensationhKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
file size:37,130 KBhKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Y: PSNR: 37.8778 43.1724 49.8913hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
U: PSNR: 37.6963 44.2841 50.6220hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
V: PSNR: 38.1674 44.5764 51.4783hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Sum: PSNR: 38.3576 43.5519 50.0746
#T}I6ZS@QD6本文来自:V电G玩S天K空Yfile size:37,130 KBhKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Y: PSNR: 37.8778 43.1724 49.8913hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
U: PSNR: 37.6963 44.2841 50.6220hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
V: PSNR: 38.1674 44.5764 51.4783hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Sum: PSNR: 38.3576 43.5519 50.0746
x264 core:42 svn-388 + patchs
QUOTE:
x264.exe --keyint 300 --min-keyint 24 --bframe 3 --b-pyramid --nf --analyse "none" --weightb --me "dia" --subme 1 --pass 1 --stats "x264_2pass.log" --qcomp 0.7 --bitrate 1033 --qpstep 32 --ratetol inf --progress --output NUL --no-psnr --quiet "17.avs"hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
x264.exe --keyint 300 --min-keyint 24 --bframe 3 --b-pyramid --ref 16 --nf --analyse "all" --weightb --me "umh" --merange 64 --subme 7 --b-rdo --mixed-refs --8x8dct --trellis 2 --no-fast-pskip --pass 2 --stats "x264_2pass.log" --qcomp 0.7 --bitrate 1033 --qpstep 32 --progress --output 17.mp4 "17.avs" hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
file size:37,189 KBhKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Y: PSNR: 39.8436 44.9354 49.9480hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
U: PSNR: 39.5507 45.5019 51.1331hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
V: PSNR: 39.6453 45.7164 51.4455hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Sum: PSNR: 39.8308 45.1482 50.0778
#T}I6ZS@QD6本文来自:V电G玩S天K空Yx264.exe --keyint 300 --min-keyint 24 --bframe 3 --b-pyramid --ref 16 --nf --analyse "all" --weightb --me "umh" --merange 64 --subme 7 --b-rdo --mixed-refs --8x8dct --trellis 2 --no-fast-pskip --pass 2 --stats "x264_2pass.log" --qcomp 0.7 --bitrate 1033 --qpstep 32 --progress --output 17.mp4 "17.avs" hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
file size:37,189 KBhKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Y: PSNR: 39.8436 44.9354 49.9480hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
U: PSNR: 39.5507 45.5019 51.1331hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
V: PSNR: 39.6453 45.7164 51.4455hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
Sum: PSNR: 39.8308 45.1482 50.0778
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y
hKpW%0t;j54]+3Ih|yBk~+KN_*3#Q4kkP]fzai))F=eay];.n~-xp0Vq5-/)]m7xdL6*1jfi$QAkcguW*i]g#eJhtRtk本文来自:V电G玩S天K空Y


