文章目录
这是因为我们把海康rtsp视频流packet解封装后，它frame的像素格式是yuvj420p（AV_PIX_FMT_YUVJ420P）的，然后我们又指定编码器上下文的像素格式pix_fmt = AV_PIX_FMT_YUVJ420P，指定编码器为AV_CODEC_ID_MPEG4，但是AV_CODEC_ID_MPEG4不支持AV_PIX_FMT_YUVJ420P像素格式，所以报了上述错误
用ffmpeg -h encoder=mpeg4指令查看编码器支持哪些像素格式
发现：
x264编码器支持yuv420p yuvj420p yuv422p yuvj422p yuv444p yuvj444p nv12 nv16 nv21 yuv420p10le yuv422p10le yuv444p10le nv20le gray gray10le
x265编码器支持yuv420p yuvj420p yuv422p yuvj422p yuv444p yuvj444p gbrp yuv420p10le yuv422p10le yuv444p10le gbrp10le yuv420p12le yuv422p12le yuv444p12le gbrp12le gray gray10le gray12le
mpeg4编码器支持yuv420p
那么解决方法只能是
①将yuvj420p的frame转换成yuv420p的frame，再输入给mpeg4编码器（我不知道ffmpeg有没这个功能。。。）
②换个编码器，比如x264或x265，它们都支持解析yuvj420p，同时能将输出packet的像素格式转换成其他的类型，比如yuv420p
C:\Users\Arnold\source\repos\20221114_ffmpeg_compile_test2\video>ffmpeg -h encoder=libx264
ffmpeg version n4.3.2-162-g4bbcaf7559 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 9.3-win32 (GCC) 20200320
configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 --enable-gpl --enable-version3 --disable-debug --enable-shared --disable-static --disable-w32threads --enable-pthreads --enable-iconv --enable-zlib --enable-libxml2 --enable-libfreetype --enable-libfribidi --enable-gmp --enable-lzma --enable-fontconfig --enable-opencl --enable-libvmaf --disable-vulkan --enable-libvorbis --enable-amf --enable-libaom --enable-avisynth --enable-libdav1d --enable-libdavs2 --enable-ffnvcodec --enable-cuda-llvm --disable-libglslang --enable-libgme --enable-libass --enable-libbluray --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvpx --enable-libwebp --enable-lv2 --enable-libmfx --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librav1e --enable-librubberband --enable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libtwolame --enable-libvidstab --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libzimg --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-libs=-lgomp
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
libpostproc 55. 7.100 / 55. 7.100
Encoder libx264 [libx264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10]:
General capabilities: delay threads
Threading capabilities: auto
Supported pixel formats: yuv420p yuvj420p yuv422p yuvj422p yuv444p yuvj444p nv12 nv16 nv21 yuv420p10le yuv422p10le yuv444p10le nv20le gray gray10le
libx264 AVOptions:
-preset <string> E..V...... Set the encoding preset (cf. x264 --fullhelp) (default "medium")
-tune <string> E..V...... Tune the encoding params (cf. x264 --fullhelp)
-profile <string> E..V...... Set profile restrictions (cf. x264 --fullhelp)
-fastfirstpass <boolean> E..V...... Use fast settings when encoding first pass (default true)
-level <string> E..V...... Specify level (as defined by Annex A)
-passlogfile <string> E..V...... Filename for 2 pass stats
-wpredp <string> E..V...... Weighted prediction for P-frames
-a53cc <boolean> E..V...... Use A53 Closed Captions (if available) (default true)
-x264opts <string> E..V...... x264 options
-crf <float> E..V...... Select the quality for constant quality mode (from -1 to FLT_MAX) (default -1)
-crf_max <float> E..V...... In CRF mode, prevents VBV from lowering quality beyond this point. (from -1 to FLT_MAX) (default -1)
-qp <int> E..V...... Constant quantization parameter rate control method (from -1 to INT_MAX) (default -1)
-aq-mode <int> E..V...... AQ method (from -1 to INT_MAX) (default -1)
none 0 E..V......
variance 1 E..V...... Variance AQ (complexity mask)
autovariance 2 E..V...... Auto-variance AQ
autovariance-biased 3 E..V...... Auto-variance AQ with bias to dark scenes
-aq-strength <float> E..V...... AQ strength. Reduces blocking and blurring in flat and textured areas. (from -1 to FLT_MAX) (default -1)
-psy <boolean> E..V...... Use psychovisual optimizations. (default auto)
-psy-rd <string> E..V...... Strength of psychovisual optimization, in <psy-rd>:<psy-trellis> format.
-rc-lookahead <int> E..V...... Number of frames to look ahead for frametype and ratecontrol (from -1 to INT_MAX) (default -1)
-weightb <boolean> E..V...... Weighted prediction for B-frames. (default auto)
-weightp <int> E..V...... Weighted prediction analysis method. (from -1 to INT_MAX) (default -1)
none 0 E..V......
simple 1 E..V......
smart 2 E..V......
-ssim <boolean> E..V...... Calculate and print SSIM stats. (default auto)
-intra-refresh <boolean> E..V...... Use Periodic Intra Refresh instead of IDR frames. (default auto)
-bluray-compat <boolean> E..V...... Bluray compatibility workarounds. (default auto)
-b-bias <int> E..V...... Influences how often B-frames are used (from INT_MIN to INT_MAX) (default INT_MIN)
-b-pyramid <int> E..V...... Keep some B-frames as references. (from -1 to INT_MAX) (default -1)
none 0 E..V......
strict 1 E..V...... Strictly hierarchical pyramid
normal 2 E..V...... Non-strict (not Blu-ray compatible)
-mixed-refs <boolean> E..V...... One reference per partition, as opposed to one reference per macroblock (default auto)
-8x8dct <boolean> E..V...... High profile 8x8 transform. (default auto)
-fast-pskip <boolean> E..V...... (default auto)
-aud <boolean> E..V...... Use access unit delimiters. (default auto)
-mbtree <boolean> E..V...... Use macroblock tree ratecontrol. (default auto)
-deblock <string> E..V...... Loop filter parameters, in <alpha:beta> form.
-cplxblur <float> E..V...... Reduce fluctuations in QP (before curve compression) (from -1 to FLT_MAX) (default -1)
-partitions <string> E..V...... A comma-separated list of partitions to consider. Possible values: p8x8, p4x4, b8x8, i8x8, i4x4, none, all
-direct-pred <int> E..V...... Direct MV prediction mode (from -1 to INT_MAX) (default -1)
none 0 E..V......
spatial 1 E..V......
temporal 2 E..V......
auto 3 E..V......
-slice-max-size <int> E..V...... Limit the size of each slice in bytes (from -1 to INT_MAX) (default -1)
-stats <string> E..V...... Filename for 2 pass stats
-nal-hrd <int> E..V...... Signal HRD information (requires vbv-bufsize; cbr not allowed in .mp4) (from -1 to INT_MAX) (default -1)
none 0 E..V......
vbr 1 E..V......
cbr 2 E..V......
-avcintra-class <int> E..V...... AVC-Intra class 50/100/200 (from -1 to 200) (default -1)
-me_method <int> E..V...... Set motion estimation method (from -1 to 4) (default -1)
dia 0 E..V......
hex 1 E..V......
umh 2 E..V......
esa 3 E..V......
tesa 4 E..V......
-motion-est <int> E..V...... Set motion estimation method (from -1 to 4) (default -1)
dia 0 E..V......
hex 1 E..V......
umh 2 E..V......
esa 3 E..V......
tesa 4 E..V......
-forced-idr <boolean> E..V...... If forcing keyframes, force them as IDR frames. (default false)
-coder <int> E..V...... Coder type (from -1 to 1) (default default)
default -1 E..V......
cavlc 0 E..V......
cabac 1 E..V......
vlc 0 E..V......
ac 1 E..V......
-b_strategy <int> E..V...... Strategy to choose between I/P/B-frames (from -1 to 2) (default -1)
-chromaoffset <int> E..V...... QP difference between chroma and luma (from INT_MIN to INT_MAX) (default -1)
-sc_threshold <int> E..V...... Scene change threshold (from INT_MIN to INT_MAX) (default -1)
-noise_reduction <int> E..V...... Noise reduction (from INT_MIN to INT_MAX) (default -1)
-x264-params <dictionary> E..V...... Override the x264 configuration using a :-separated list of key=value parameters
C:\Users\Arnold\source\repos\20221114_ffmpeg_compile_test2\video>ffmpeg -h encoder=libx265
ffmpeg version n4.3.2-162-g4bbcaf7559 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 9.3-win32 (GCC) 20200320
configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 --enable-gpl --enable-version3 --disable-debug --enable-shared --disable-static --disable-w32threads --enable-pthreads --enable-iconv --enable-zlib --enable-libxml2 --enable-libfreetype --enable-libfribidi --enable-gmp --enable-lzma --enable-fontconfig --enable-opencl --enable-libvmaf --disable-vulkan --enable-libvorbis --enable-amf --enable-libaom --enable-avisynth --enable-libdav1d --enable-libdavs2 --enable-ffnvcodec --enable-cuda-llvm --disable-libglslang --enable-libgme --enable-libass --enable-libbluray --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvpx --enable-libwebp --enable-lv2 --enable-libmfx --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librav1e --enable-librubberband --enable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libtwolame --enable-libvidstab --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libzimg --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-libs=-lgomp
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
libpostproc 55. 7.100 / 55. 7.100
Encoder libx265 [libx265 H.265 / HEVC]:
General capabilities: delay threads
Threading capabilities: auto
Supported pixel formats: yuv420p yuvj420p yuv422p yuvj422p yuv444p yuvj444p gbrp yuv420p10le yuv422p10le yuv444p10le gbrp10le yuv420p12le yuv422p12le yuv444p12le gbrp12le gray gray10le gray12le
libx265 AVOptions:
-crf <float> E..V...... set the x265 crf (from -1 to FLT_MAX) (default -1)
-qp <int> E..V...... set the x265 qp (from -1 to INT_MAX) (default -1)
-forced-idr <boolean> E..V...... if forcing keyframes, force them as IDR frames (default false)
-preset <string> E..V...... set the x265 preset
-tune <string> E..V...... set the x265 tune parameter
-profile <string> E..V...... set the x265 profile
-x265-params <dictionary> E..V...... set the x265 configuration using a :-separated list of key=value parameters
C:\Users\Arnold\source\repos\20221114_ffmpeg_compile_test2\video>
C:\Users\Arnold\source\repos\20221114_ffmpeg_compile_test2\video>ffmpeg -h encoder=mpeg4
ffmpeg version n4.3.2-162-g4bbcaf7559 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 9.3-win32 (GCC) 20200320
configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 --enable-gpl --enable-version3 --disable-debug --enable-shared --disable-static --disable-w32threads --enable-pthreads --enable-iconv --enable-zlib --enable-libxml2 --enable-libfreetype --enable-libfribidi --enable-gmp --enable-lzma --enable-fontconfig --enable-opencl --enable-libvmaf --disable-vulkan --enable-libvorbis --enable-amf --enable-libaom --enable-avisynth --enable-libdav1d --enable-libdavs2 --enable-ffnvcodec --enable-cuda-llvm --disable-libglslang --enable-libgme --enable-libass --enable-libbluray --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvpx --enable-libwebp --enable-lv2 --enable-libmfx --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librav1e --enable-librubberband --enable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libtwolame --enable-libvidstab --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libzimg --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-libs=-lgomp
libavutil 56. 51.100 / 56. 51.100
libavcodec 58. 91.100 / 58. 91.100
libavformat 58. 45.100 / 58. 45.100
libavdevice 58. 10.100 / 58. 10.100
libavfilter 7. 85.100 / 7. 85.100
libswscale 5. 7.100 / 5. 7.100
libswresample 3. 7.100 / 3. 7.100
libpostproc 55. 7.100 / 55. 7.100
Encoder mpeg4 [MPEG-4 part 2]:
General capabilities: delay threads
Threading capabilities: slice
Supported pixel formats: yuv420p
MPEG4 encoder AVOptions:
-data_partitioning <boolean> E..V...... Use data partitioning. (default false)
-alternate_scan <boolean> E..V...... Enable alternate scantable. (default false)
-mpv_flags <flags> E..V...... Flags common for all mpegvideo-based encoders. (default 0)
skip_rd E..V...... RD optimal MB level residual skipping
strict_gop E..V...... Strictly enforce gop size
qp_rd E..V...... Use rate distortion optimization for qp selection
cbp_rd E..V...... use rate distortion optimization for CBP
naq E..V...... normalize adaptive quantization
mv0 E..V...... always try a mb with mv=<0,0>
-luma_elim_threshold <int> E..V...... single coefficient elimination threshold for luminance (negative values also consider dc coefficient) (from INT_MIN to INT_MAX) (default 0)
-chroma_elim_threshold <int> E..V...... single coefficient elimination threshold for chrominance (negative values also consider dc coefficient) (from INT_MIN to INT_MAX) (default 0)
-quantizer_noise_shaping <int> E..V...... (from 0 to INT_MAX) (default 0)
-error_rate <int> E..V...... Simulate errors in the bitstream to test error concealment. (from 0 to INT_MAX) (default 0)
-qsquish <float> E..V...... how to keep quantizer between qmin and qmax (0 = clip, 1 = use differentiable function) (from 0 to 99) (default 0)
-rc_qmod_amp <float> E..V...... experimental quantizer modulation (from -FLT_MAX to FLT_MAX) (default 0)
-rc_qmod_freq <int> E..V...... experimental quantizer modulation (from INT_MIN to INT_MAX) (default 0)
-rc_eq <string> E..V...... Set rate control equation. When computing the expression, besides the standard functions defined in the section 'Expression Evaluation', the following functions are available: bits2qp(bits), qp2bits(qp). Also the following constants are available: iTex pTex tex mv fCode iCount mcVar var isI isP isB avgQP qComp avgIITex avgPITex avgPPTex avgBPTex avgTex.
-rc_init_cplx <float> E..V...... initial complexity for 1-pass encoding (from -FLT_MAX to FLT_MAX) (default 0)
-rc_buf_aggressivity <float> E..V...... currently useless (from -FLT_MAX to FLT_MAX) (default 1)
-border_mask <float> E..V...... increase the quantizer for macroblocks close to borders (from -FLT_MAX to FLT_MAX) (default 0)
-lmin <int> E..V...... minimum Lagrange factor (VBR) (from 0 to INT_MAX) (default 236)
-lmax <int> E..V...... maximum Lagrange factor (VBR) (from 0 to INT_MAX) (default 3658)
-ibias <int> E..V...... intra quant bias (from INT_MIN to INT_MAX) (default 999999)
-pbias <int> E..V...... inter quant bias (from INT_MIN to INT_MAX) (default 999999)
-rc_strategy <int> E..V...... ratecontrol method (from 0 to 1) (default ffmpeg)
ffmpeg 0 E..V...... deprecated, does nothing
xvid 0 E..V...... deprecated, does nothing
-motion_est <int> E..V...... motion estimation algorithm (from 0 to 2) (default epzs)
zero 0 E..V......
epzs 1 E..V......
xone 2 E..V......
-force_duplicated_matrix <boolean> E..V...... Always write luma and chroma matrix for mjpeg, useful for rtp streaming. (default false)
-b_strategy <int> E..V...... Strategy to choose between I/P/B-frames (from 0 to 2) (default 0)
-b_sensitivity <int> E..V...... Adjust sensitivity of b_frame_strategy 1 (from 1 to INT_MAX) (default 40)
-brd_scale <int> E..V...... Downscale frames for dynamic B-frame decision (from 0 to 3) (default 0)
-skip_threshold <int> E..V...... Frame skip threshold (from INT_MIN to INT_MAX) (default 0)
-skip_factor <int> E..V...... Frame skip factor (from INT_MIN to INT_MAX) (default 0)
-skip_exp <int> E..V...... Frame skip exponent (from INT_MIN to INT_MAX) (default 0)
-skip_cmp <int> E..V...... Frame skip compare function (from INT_MIN to INT_MAX) (default dctmax)
sad 0 E..V...... Sum of absolute differences, fast
sse 1 E..V...... Sum of squared errors
satd 2 E..V...... Sum of absolute Hadamard transformed differences
dct 3 E..V...... Sum of absolute DCT transformed differences
psnr 4 E..V...... Sum of squared quantization errors, low quality
bit 5 E..V...... Number of bits needed for the block
rd 6 E..V...... Rate distortion optimal, slow
zero 7 E..V...... Zero
vsad 8 E..V...... Sum of absolute vertical differences
vsse 9 E..V...... Sum of squared vertical differences
nsse 10 E..V...... Noise preserving sum of squared differences
dct264 14 E..V......
dctmax 13 E..V......
chroma 256 E..V......
msad 15 E..V...... Sum of absolute differences, median predicted
-sc_threshold <int> E..V...... Scene change threshold (from INT_MIN to INT_MAX) (default 0)
-noise_reduction <int> E..V...... Noise reduction (from INT_MIN to INT_MAX) (default 0)
-mpeg_quant <int> E..V...... Use MPEG quantizers instead of H.263 (from 0 to 1) (default 0)
-ps <int> E..V...... RTP payload size in bytes (from INT_MIN to INT_MAX) (default 0)
-mepc <int> E..V...... Motion estimation bitrate penalty compensation (1.0 = 256) (from INT_MIN to INT_MAX) (default 256)
-mepre <int> E..V...... pre motion estimation (from INT_MIN to INT_MAX) (default 0)
-intra_penalty <int> E..V...... Penalty for intra blocks in block decision (from 0 to 1.07374e+09) (default 0)
-a53cc <boolean> E..V...... Use A53 Closed Captions (if available) (default true)
C:\Users\Arnold\source\repos\20221114_ffmpeg_compile_test2\video>
我在我们英伟达8核盒子上查看
x264编码：
ffmpeg -h encoder=h264
我想用ruby编写一个小的命令行实用程序并将其作为gem分发。我知道安装后，Guard、Sass和Thor等某些gem可以从命令行自行运行。为了让gem像二进制文件一样可用，我需要在我的gemspec中指定什么。 最佳答案 Gem::Specification.newdo|s|...s.executable='name_of_executable'...endhttp://docs.rubygems.org/read/chapter/20 关于ruby-在Ruby中编写命令行实用程序
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有这样的事吗？我想在Ruby程序中使用它。 最佳答案 试试这个http://csl.sublevel3.org/jp2a/此外，Imagemagick可能还有一些东西 关于ruby-是否有将图像文件转换为ASCII艺术的命令行程序或库？，我们在StackOverflow上找到一个类似的问题： https://stackoverflow.com/questions/6510445/
如何在Ruby的if语句中检查bash命令的返回值(true/false)。我想要这样的东西，if("/usr/bin/fswscell>/dev/null2>&1")has_afs="true"elsehas_afs="false"end它会提示以下错误含义，它总是返回true。(irb):5:warning:stringliteralincondition正确的语法是什么？更新:/usr/bin/fswscell寻找afs安装和运行状态。它会抛出这样的字符串，Thisworkstationbelongstocell如果afs没有运行，命令以状态1退出 最
在几个项目中，我希望有一个类似rakeserver的rake任务，它将通过任何需要的方式开始为该应用程序提供服务。这是一个示例:task:serverdo%x{bundleexecrackup-p1234}end这行得通，但是当我准备停止它时，按Ctrl+c并没有正常关闭；它中断了Rake任务本身，它说rakeaborted!并给出堆栈跟踪。在某些情况下，我必须执行Ctrl+c两次。我可能可以用Signal.trap写一些东西来更优雅地中断它。有没有更简单的方法？ 最佳答案 trap('SIGINT'){puts"Yourmessa