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354 lines
24 KiB
354 lines
24 KiB
<a href="/blog">
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{% load static %}
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<div class="bottom_right_div"><img src="{% static '2hu.png' %}"></div>
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</a>
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<div id="overlay" aria-hidden="true" onclick="removefull()"></div>
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<div class="wrapper_article">
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<p class="heading">Why and how to use x265</p>
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<div class="content">
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<ul>
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<li><a href="#c_introduction">Introduction</a></li>
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<li><a href="#filesize">File size comparision</a></li>
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<li><a href="#settings">Useful parameters for encoding with x265</a></li>
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</ul>
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</div>
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<p class="subhead"><a href="#c_introduction" id="c_introduction">Introduction</a></p>
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<div class="content">
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For many years x264 has been the standard video codec for video encoding and achieved the best results one
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could get in terms of video compression and efficiency. But in 2013, when the initial version of x265
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was released, it yielded far better results than were previously possible with x264. Now 2.0 stable version of
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x265 is released and we are a few CPU and GPU generations farther than we were in 2013.
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Additionally, the new PCs, notebooks, and even smartphones that are coming out are all receiving native
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hardware support for decoding x265, so as of today, more and more people
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can view HEVC encoded videos just the same as they can view AVC encoded videos.
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The problem is that the encoders in the fansubbing community are only slowly adapting to
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the new codec, effectively wasting the bandwidth of the viewer, or offering a lower quality than they could achieve
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with x265. <br>
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In the following section, I will explain why HEVC/x265 is superior to x264/AVC and why you should use it to encode your
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videos.
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</div>
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<p class="subhead"><a id="filesize" href="#filesize">File size comparison</a></p>
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<div class="content">
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This section will be dedicated to comparing the difference in filesize between x264 and x265.
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For x265, I used CRF 17 and the veryslow preset, which already yields very good results.
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For x264, I used CRF 15, the preset veryslow and the parameters subme 11, me tesa, merange 32, and bframes 16.<br>
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Both encodes also have aq-mode 3 enabled.<br>
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Please note: CRF in x264 and x265 is NOT comparable, both encoders use a different way to calculate the CRF.
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I found CRF 15 for x264 and CRF 17 for x265 to have nearly the same quality, but results may vary.
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You have been warned. <br>
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<table class="two_column_table">
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<tr>
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<td><img class="img_expandable rounded" src="/media/articles/res_mr/onepunchmane1f13487x264crf15.png"></td>
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<td><img class="img_expandable rounded" src="/media/articles/res_mr/onepunchmane1f13487x265crf17.png"></td>
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</tr>
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<tr>
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<td>One Punch Man episode 1, frame 13487 at CRF 15 in x264</td>
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<td>And here in x265 at CRF 17</td>
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</tr>
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</table>
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<br>
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<p>
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1. Static videos: The test clip consists of the first 1000 frames of Non Non Byori Repeat episode 1.<br><br>
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<a href="/media/articles/res_mr/NNBR_Encodes.zip">Download the encodes</a><br>
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</p>
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<br>
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Logfiles of the encodes (expandable):<br>
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<div class="spoilerbox_expand_element">x264 log
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<p class="code">
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x264 [info]: 1920x1080p 0:0 @ 24000/1001 fps (cfr)<br>
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x264 [info]: color matrix: undef<br>
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x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX<br>
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x264 [info]: AVC Encoder x264 core 148 r2699+6+41 29a38aa Yuuki [10-bit@all X86_64][GCC 5.3.0]<br>
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x264 [info]: profile: High 10, level: 5.1, subsampling: 4:2:0, bit-depth: 10-bit<br>
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x264 [info]: cabac=1 ref=16 deblock=1:0:-1 analyse=0x3:0x133 me=tesa subme=11 psy=1 fade_compensate=0.00 psy_rd=1.00:0.00 mixed_ref=1 me_range=32 chroma_me=1 trellis=2 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=0 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=0 interlaced=0 bluray_compat=0 constrained_intra=0 fgo=0 bframes=16 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=23 scenecut=40 intra_refresh=0 rc_lookahead=60 rc=crf mbtree=1 crf=15.0000 qcomp=0.60 qpmin=0:0:0 qpmax=81:81:81 qpstep=4 ip_ratio=1.40 aq=3:0.80<br>
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x264 [info]: started at Sun Aug 07 23:46:37 2016<br>
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x264 [info]: frame I:10 Avg QP:22.52 size:391771<br>
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x264 [info]: frame P:236 Avg QP:26.76 size: 70531<br>
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x264 [info]: frame B:754 Avg QP:28.05 size: 7533<br>
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x264 [info]: consecutive B-frames: 1.1% 2.0% 45.0% 3.2% 6.0% 12.0% 4.2% 11.2% 8.1% 2.0% 1.1% 2.4% 0.0% 0.0% 0.0% 0.0% 1.7%<br>
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x264 [info]: mb I I16..4: 49.8% 28.1% 22.1%<br>
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x264 [info]: mb P I16..4: 4.6% 0.7% 0.7% P16..4: 44.1% 28.7% 10.7% 1.6% 0.2% skip: 8.7%<br>
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x264 [info]: mb B I16..4: 0.4% 0.0% 0.1% B16..8: 28.4% 4.8% 0.3% direct: 1.5% skip:64.5% L0:42.1% L1:55.0% BI: 2.8%<br>
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x264 [info]: 8x8 transform intra:16.7% inter:41.3%<br>
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x264 [info]: direct mvs spatial:98.5% temporal:1.5%<br>
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x264 [info]: coded y,uvDC,uvAC intra: 89.9% 87.5% 81.4% inter: 11.0% 15.1% 7.0%<br>
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x264 [info]: i16 v,h,dc,p: 14% 10% 18% 57%<br>
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x264 [info]: i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 22% 12% 8% 8% 9% 11% 10% 9% 10%<br>
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x264 [info]: i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 19% 8% 30% 6% 7% 7% 7% 7% 9%<br>
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x264 [info]: i8c dc,h,v,p: 52% 18% 11% 18%<br>
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x264 [info]: Weighted P-Frames: Y:3.0% UV:3.0%<br>
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x264 [info]: ref P L0: 58.3% 19.9% 5.7% 4.1% 1.6% 3.0% 1.3% 1.2% 0.6% 1.0% 0.6% 0.9% 0.5% 0.8% 0.5% 0.0%<br>
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x264 [info]: ref B L0: 71.8% 11.7% 5.5% 2.5% 1.8% 1.7% 1.3% 0.7% 0.6% 0.5% 0.5% 0.5% 0.4% 0.3% 0.1%<br>
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x264 [info]: ref B L1: 97.1% 2.9%<br>
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x264 [info]: kb/s:5033.59<br>
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x264 [info]: encoded 1000 frames, 0.5356 fps, 5033.74 kb/s, 25.03 MB<br>
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x264 [info]: ended at Mon Aug 08 00:17:44 2016<br>
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x264 [info]: encoding duration 0:31:07<br>
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</p>
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</div>
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<div class="spoilerbox_expand_element">x265 log
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<p class="code">
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yuv [info]: 1920x1080 fps 24000/1001 i420p8 unknown frame count<br>
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x265 [info]: Using preset veryslow & tune none<br>
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x265 [info]: HEVC encoder version 2.0M+9-g457336f+14<br>
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x265 [info]: build info [Windows][GCC 5.3.0][64 bit] Yuuki 10bit<br>
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x265 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX<br>
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x265 [info]: Main 10 profile, Level-4 (Main tier)<br>
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x265 [info]: Thread pool created using 4 threads<br>
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x265 [info]: frame threads / pool features : 2 / wpp(17 rows)<br>
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x265 [info]: Coding QT: max CU size, min CU size : 64 / 8<br>
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x265 [info]: Residual QT: max TU size, max depth : 32 / 3 inter / 3 intra<br>
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x265 [info]: ME / range / subpel / merge : star / 57 / 4 / 4<br>
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x265 [info]: Keyframe min / max / scenecut : 23 / 250 / 40<br>
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x265 [info]: Lookahead / bframes / badapt : 40 / 8 / 2<br>
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x265 [info]: b-pyramid / weightp / weightb : 1 / 1 / 1<br>
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x265 [info]: References / ref-limit cu / depth : 5 / off / on<br>
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x265 [info]: AQ: mode / str / qg-size / cu-tree : 3 / 1.0 / 32 / 1<br>
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x265 [info]: Rate Control / qCompress : CRF-17.0 / 0.60<br>
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x265 [info]: tools: rect amp limit-modes rd=6 psy-rd=2.00 rdoq=2 psy-rdoq=1.00<br>
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x265 [info]: tools: rskip signhide tmvp b-intra strong-intra-smoothing deblock<br>
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x265 [info]: tools: sao<br>
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x265 [info]: frame I: 9, Avg QP:14.24 kb/s: 32406.31<br>
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x265 [info]: frame P: 178, Avg QP:14.40 kb/s: 6617.61<br>
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x265 [info]: frame B: 813, Avg QP:23.03 kb/s: 326.86<br>
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x265 [info]: Weighted P-Frames: Y:12.4% UV:12.4%<br>
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x265 [info]: Weighted B-Frames: Y:14.9% UV:14.3%<br>
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x265 [info]: consecutive B-frames: 5.9% 1.1% 21.4% 2.7% 9.6% 36.9% 4.8% 10.2% 7.5%<br>
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encoded 1000 frames in 1010.58s (0.99 fps), 1735.33 kb/s, Avg QP:21.41<br>
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</p>
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</div>
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<p>
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The x264 encode has an average bitrate of 5033.74 kb/s resulting in a total filesize of 25.03 MB, while
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the x265 encode has an average bitrate of 1735.33 kb/s resulting in a total filesize of 8.64 MB. This is an 66%
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reduction, meaning the x265 file has only 1/3th the size of the x264 file whilst having the same visual quality.
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</p>
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<br>
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<p>
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2. High-motion videos: The test clip consists of 1000 frames of One Punch Man episode 1, beginning at frame 13000.<br><br>
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<a href="/media/articles/res_mr/OPM_Encodes.zip">Download the encodes</a><br><br>
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</p>
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<br>
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Logfiles of the encodes (expandable):<br>
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<div class="spoilerbox_expand_element">x264 log
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<p class="code">
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x264 [info]: 1920x1080p 0:0 @ 24000/1001 fps (cfr)<br>
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x264 [info]: color matrix: undef<br>
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x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX<br>
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x264 [info]: AVC Encoder x264 core 148 r2699+6+41 29a38aa Yuuki [10-bit@all X86_64][GCC 5.3.0]<br>
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x264 [info]: profile: High 10, level: 5.1, subsampling: 4:2:0, bit-depth: 10-bit<br>
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x264 [info]: cabac=1 ref=16 deblock=1:0:-1 analyse=0x3:0x133 me=tesa subme=11 psy=1 fade_compensate=0.00 psy_rd=1.00:0.00 mixed_ref=1 me_range=32 chroma_me=1 trellis=2 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=0 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=0 interlaced=0 bluray_compat=0 constrained_intra=0 fgo=0 bframes=16 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=23 scenecut=40 intra_refresh=0 rc_lookahead=60 rc=crf mbtree=1 crf=15.0000 qcomp=0.60 qpmin=0:0:0 qpmax=81:81:81 qpstep=4 ip_ratio=1.40 aq=3:0.80<br>
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x264 [info]: started at Mon Aug 08 01:49:11 2016<br>
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x264 [info]: frame I:8 Avg QP:25.24 size:284336<br>
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x264 [info]: frame P:285 Avg QP:28.03 size: 95640<br>
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x264 [info]: frame B:707 Avg QP:28.83 size: 40806<br>
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x264 [info]: consecutive B-frames: 2.9% 5.4% 26.7% 44.8% 9.0% 9.0% 1.4% 0.8% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%<br>
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x264 [info]: mb I I16..4: 0.5% 95.9% 3.6%<br>
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x264 [info]: mb P I16..4: 0.5% 13.6% 1.3% P16..4: 35.8% 34.5% 12.1% 1.2% 0.1% skip: 1.0%<br>
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x264 [info]: mb B I16..4: 0.1% 3.9% 0.1% B16..8: 37.8% 17.5% 2.6% direct: 8.1% skip:29.9% L0:53.2% L1:42.1% BI: 4.8%<br>
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x264 [info]: 8x8 transform intra:91.7% inter:78.2%<br>
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x264 [info]: direct mvs spatial:99.6% temporal:0.4%<br>
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x264 [info]: coded y,uvDC,uvAC intra: 90.3% 91.1% 74.3% inter: 34.2% 38.3% 10.4%<br>
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x264 [info]: i16 v,h,dc,p: 12% 22% 10% 55%<br>
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x264 [info]: i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 11% 7% 16% 10% 12% 11% 11% 10% 12%<br>
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x264 [info]: i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 11% 9% 3% 11% 18% 14% 13% 10% 11%<br>
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x264 [info]: i8c dc,h,v,p: 47% 20% 19% 14%<br>
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x264 [info]: Weighted P-Frames: Y:9.1% UV:7.0%<br>
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x264 [info]: ref P L0: 41.9% 17.7% 9.6% 5.6% 5.2% 4.0% 2.8% 2.1% 1.5% 1.8% 2.1% 2.0% 1.4% 1.1% 0.9% 0.1%<br>
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x264 [info]: ref B L0: 58.4% 11.5% 6.4% 4.0% 2.8% 4.0% 2.6% 1.5% 1.4% 1.4% 1.1% 2.0% 1.6% 1.0% 0.3%<br>
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x264 [info]: ref B L1: 95.8% 4.2%<br>
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x264 [info]: kb/s:11198.17<br>
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x264 [info]: encoded 1000 frames, 0.2929 fps, 11198.33 kb/s, 55.68 MB<br>
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x264 [info]: ended at Mon Aug 08 02:46:06 2016<br>
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x264 [info]: encoding duration 0:56:55<br>
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</p>
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</div>
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<div class="spoilerbox_expand_element">x265 log
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<p class="code">
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yuv [info]: 1920x1080 fps 24000/1001 i420p8 unknown frame count<br>
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x265 [info]: Using preset veryslow & tune none<br>
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x265 [info]: HEVC encoder version 2.0M+9-g457336f+14<br>
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x265 [info]: build info [Windows][GCC 5.3.0][64 bit] Yuuki 10bit<br>
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x265 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX<br>
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x265 [info]: Main 10 profile, Level-4 (Main tier)<br>
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x265 [info]: Thread pool created using 4 threads<br>
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x265 [info]: frame threads / pool features : 2 / wpp(17 rows)<br>
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x265 [info]: Coding QT: max CU size, min CU size : 64 / 8<br>
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x265 [info]: Residual QT: max TU size, max depth : 32 / 3 inter / 3 intra<br>
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x265 [info]: ME / range / subpel / merge : star / 57 / 4 / 4<br>
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x265 [info]: Keyframe min / max / scenecut : 23 / 250 / 40<br>
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x265 [info]: Lookahead / bframes / badapt : 40 / 8 / 2<br>
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x265 [info]: b-pyramid / weightp / weightb : 1 / 1 / 1<br>
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x265 [info]: References / ref-limit cu / depth : 5 / off / on<br>
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x265 [info]: AQ: mode / str / qg-size / cu-tree : 3 / 1.0 / 32 / 1<br>
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x265 [info]: Rate Control / qCompress : CRF-17.0 / 0.60<br>
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x265 [info]: tools: rect amp limit-modes rd=6 psy-rd=2.00 rdoq=2 psy-rdoq=1.00<br>
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x265 [info]: tools: rskip signhide tmvp b-intra strong-intra-smoothing deblock<br>
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x265 [info]: tools: sao<br>
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x265 [info]: frame I: 14, Avg QP:14.37 kb/s: 18963.14<br>
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x265 [info]: frame P: 253, Avg QP:15.76 kb/s: 12334.19<br>
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x265 [info]: frame B: 733, Avg QP:19.84 kb/s: 3709.09<br>
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x265 [info]: Weighted P-Frames: Y:9.5% UV:8.3%<br>
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x265 [info]: Weighted B-Frames: Y:8.3% UV:6.8%<br>
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x265 [info]: consecutive B-frames: 11.6% 9.4% 14.6% 43.1% 7.1% 10.5% 1.5% 1.1% 1.1%<br>
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encoded 1000 frames in 2391.07s (0.42 fps), 6104.80 kb/s, Avg QP:18.73<br>
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</p>
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</div>
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<br>
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<p>
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The x264 encode has an average bitrate of 11198.33 kb/s resulting in a total filesize of 55.68 MB, while
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the x265 encode has an average bitrate of 6104.80 kb/s resulting in a total filesize of 30.3 MB. This is an 43%
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reduction, meaning the x265 file has only 4/7th the size of the x264 file.<br><br>
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Conclusion: x265 offers the same visual quality at significantly lower bitrates, meaning one can offer an encode with higher
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visual quality than x264 at the same filesize, or reduce the filesize of the encoded videos by a large amount while
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offering the same visual fidelity as a x264 encode. With no real downsides apart from a higher encoding time
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and slightly less compatibility there really is no reason not to use it.
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</p>
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</div>
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<p class="subhead"><a id="settings" href="#settings">Useful parameters for encoding with x265</a></p>
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<div class="content">
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<p>
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Just as with x264, x265 has many parameters you can use if you don't want to stick to the presets and
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are trying to get the best possible quality. In the following section, I will explain some of these
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parameters and how to use them. You can click on each parameter to get more information about it.<br><br>
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</p>
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<div class="spoilerbox_expand_element">--preset
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<p class="code">
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Options: ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow, placebo<br>
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What it does: The further to the right the preset on this list is, the higher the compression efficiency will be at the cost of slowing down your encode.<br>
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What to use: Medium or slower are fine, but I would recommend slow or veryslow depending on how strong your encoding rig is.
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Don't use placebo, it will result in greatly increased encoding time with diminishing returns in comparison to veryslow.
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</p>
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</div>
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<div class="spoilerbox_expand_element">--ref
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<p class="code">
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Options: An integer from 1 to 16<br>
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What it does: Max number of L0 references to be allowed. This number has a linear multiplier effect on the amount of work performed in motion search.<br>
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What to use: If --b-pyramid is enabled(which is the default option), the HEVC specification only allows
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ref 6 as a maximum, without --b-pyramid the maximum ref allowed by the specification is 7. Generally, you
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want to use the highest number possible(within the specification), as it yields the best results.
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</p>
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</div>
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<div class="spoilerbox_expand_element">--rd
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<p class="code">
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Options: An integer from 1 to 6<br>
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What it does: The higher the value, the more exhaustive the RDO analysis is and the more rate distortion optimizations are used.<br>
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What to use: The highest option you can afford, in general the rule: "the lower the value the faster the encode,
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the higher the value the smaller the bitstream" applies. Please notice that, in the current version, rd 3 and 4 and rd 5 and 6 are the same.
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</p>
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</div>
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<div class="spoilerbox_expand_element">--ctu
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<p class="code">
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Options: 64,32,16<br>
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What it does: CTUs and CUs are the logical units in which the HEVC encoder divides a given picture. This
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option sets the maximum CU size.<br>
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What to use: No reason not to use 64, as it will give you large reductions in bitrate compared to the other two options
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with an insignificant increase in computing time.
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</p>
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</div>
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<div class="spoilerbox_expand_element">--min-cu-size
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<p class="code">
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Options: 64,32,16,8<br>
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What it does: CTUs and CUs are the logical units in which the HEVC encoder divides a given picture. This
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option sets the minimum CU size.<br>
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What to use: Use 8, as it is an easy way to save bitrate without a significant increase in computing time.
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</p>
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</div>
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<div class="spoilerbox_expand_element">--rect, --no-rect
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<p class="code">
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What it does: Enables the analysis of rectangular motion partitions.<br>
|
|
What to use: --rect for better encode results, --no-rect for faster encoding.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--amp, --no-amp
|
|
<p class="code">
|
|
What it does: Enables the analysis of asymmetric motion partitions.<br>
|
|
What to use: --amp for better encode results, --no-amp for faster encoding.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--rskip, --no-rskip
|
|
<p class="code">
|
|
What it does: This option determines early exit from CU depth recursion.<br>
|
|
What to use: Provides minimal quality degradation at good performance gains when enabled, so you can
|
|
choose what you want.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--rdoq-level
|
|
<p class="code">
|
|
Options: 0,1,2<br>
|
|
What it does: Specifys the amount of rate-distortion analysis to use within quantization.<br>
|
|
What to use: The standard is 2, which seems pretty good.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--max-merge
|
|
<p class="code">
|
|
Options: An integer from 1 to 5<br>
|
|
What it does: Maximum number of neighbor candidate blocks that the encoder may consider for merging motion predictions.<br>
|
|
What to use: Something from 3 to 5, depending if you are aiming for a faster encode or better results.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--me
|
|
<p class="code">
|
|
Options: dia, hex, umh, star, full<br>
|
|
What it does: Motion search method. Diamond search is the simplest. Hexagon search is a little better.
|
|
Uneven Multi-Hexagon is an adaption of the search method used by x264 for slower presets.
|
|
Star is a three step search adapted from the HM encoder and full is an exhaustive search.<br>
|
|
What to use: Umh for faster encoding, star for better encode results. Dia and hex are not worth the
|
|
quality loss and full gives diminishing returns.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--subme
|
|
<p class="code">
|
|
Options: An integer from 1 to 7<br>
|
|
What it does: This is the motion search range.<br>
|
|
What to use: Something from 4 to 7, depending on whether you are going for faster encoding or better results.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--merange
|
|
<p class="code">
|
|
Options: An integer from 0 to 32768<br>
|
|
What it does: Amount of subpel refinement to perform. The higher the number the more subpel iterations and steps are performed.<br>
|
|
What to use: The standard of 57 seems quite good, you can experiment with higher values if you want, but please
|
|
keep in mind that higher values will give you diminishing returns.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--constrained-intra, --no-constrained-intra
|
|
<p class="code">
|
|
What it does: Constrained intra prediction. The general idea is to block the propagation of reference
|
|
errors that may have resulted from lossy signals.<br>
|
|
What to use: --no-constrained-intra (which is default) unless you know what you're doing.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--psy-rd
|
|
<p class="code">
|
|
Options: A float from 0 to 5.0<br>
|
|
What it does: Turning on small amounts of psy-rd and psy-rdoq will improve the perceived visual quality,
|
|
trading distortion for bitrate. If it is too high, it will introduce visual artifacts.<br>
|
|
What to use: A value between 0.5 and 1.0 is a good starting point, you can experiment with higher values if you want, but
|
|
don't overdo it unless you like visual artifacts.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--psy-rdoq
|
|
<p class="code">
|
|
Options: A float from 0 to 50.0<br>
|
|
What it does: Turning on small amounts of psy-rd and psy-rdoq will improve the perceived visual quality,
|
|
trading distortion for bitrate. High levels of psy-rdoq can double the bitrate, so be careful.<br>
|
|
What to use: You should be good to go with a value between 0 and 5.0, but I wouldn't take a value much higher
|
|
than 1.0 because I haven't done enough tests yet.
|
|
</p>
|
|
</div>
|
|
<div class="spoilerbox_expand_element">--rc-grain, --no-rc-grain
|
|
<p class="code">
|
|
What it does: This parameter strictly minimizes QP fluctuations within and across frames and removes pulsing of grain.<br>
|
|
What to use: Use this whenever you need to encode grainy scenes, otherwise leave it disabled.
|
|
</p>
|
|
</div>
|
|
</div>
|
|
</div>
|