Shulou(Shulou.com)06/03 Report--

Use ffmpeg to decode the encoded file s1.yuv generated by X264, the command is as follows: ffmpeg-s 352x288-I s1.yuv s1.mpg, you can decode the s1.yuv into a mpg file, you can use Storm Player to play, the above 352x288 is the size of the original sequence, "x" is the English letter, not "*". Attached: FFMPEG function yuv420p original image to 264 file ffmpeg-I test.yuv test.h364 Note: only if it ends with h364

1. Video and audio format conversion Ffmpeg can use any supported format and protocol as input: * for example, you can enter the YUV file: ffmpeg-I / tmp/test%d.Y / tmp/out.mpg, which will use the following files: / tmp/test0.Y, / tmp/test0.U, / tmp/test0.V

/ tmp/test1.Y, / tmp/test1.U, / tmp/test1.V, etc. * you can enter the original YUV420P file: ffmpeg-I / tmp/test.yuv / tmp/out.avi the original YUV420P file contains the original YUV polarity, each frame begins with the Y plane, followed by the U and V planes They are half the resolution of the horizontal and vertical resolution of the Y plane * you can output the original YUV420P file ffmpeg-I mydivx.avi-o hugefile.yuv * you can set several input and output files ffmpeg-I / tmp/a.wav-s 640x480-I / tmp/a.yuv / tmp/a.mpg above the command line to convert the audio file a.wav and the original YUV video file a.yuv to the mpeg file a.mpeg * you can also The command line above ffmpeg-I / tmp/a.wav-ar 22050 / tmp/a.mp2 converts the sample rate of a.wav to 22050HZ and encodes it to mpeg audio * you can also encode to several formats at the same time and establish a mapping between input and output streams ffmpeg-I / tmp/a.wav-ab 64 / tmp/a.mp2-ab 128 / tmp/b.mp2-map 0:0-map above 0:0 The command line converts an a.wav of 64Kbits to a.mp2'- map file:index' of 128kbits, defining in the order of the output streams which input stream is used for each output stream. Transcoding and decrypting VOB: ffmpeg-I snatch_1.vob-f avi-vcodec mpeg4-b 800-g 300-bf 2-acodec mp3-ab 128 snatch.avi the command line converts vob files into avi files, mpeg4 videos and mp3 audio. Notice that B frames are used in the command, so the MPEG4 stream is divx5 compatible. A GOP size of 300 means that there are INTRA frames every 10 seconds at 29.97 frames. This mapping is especially useful for DVD transcoding of audio languages. 2. Ffmpeg uses syntax ffmpeg [[options] [`- i' input_file]]. {[options] output_file}... If there is no input file, then video and audio capture will work. As a general rule, options are generally used for the next specific file. If you give the-b 64 option, the change will set the next video rate. For the original input file, formatting options may be required. By default, ffmpeg tries to convert as lossless as possible, using the same audio and video parameters as the input. 3. Option a) General option-L license-h help-fromats displays available formats, codecs, protocols. -f fmt forced to use the format fmt-I filename input file-y overwrite output file-t duration set recording time hh:mm:ss [.xxx] format also supports-ss position search to the specified time [-] hh:mm:ss [.xxx] format also supports-title string setting title-author string setting author-copyright string setting copyright-comment string setting comment- Target type sets the target file type (vcd Svcd,dvd) all formatting options (bit rate) (encode / decode and buffer size) is automatically set. You only need to enter the following:

Ffmpeg-I myfile.avi-target vcd / tmp/vcd.mpg

-hq activates the high quality setting-itsoffset offset sets the second-based time offset, which affects all subsequent input files. This offset is added to the timestamp of the input file, and defining a positive offset means that the corresponding stream is delayed by offset seconds. [-] hh:mm:ss [.xxx] format also supports b) video option-b bitrate sets bit rate, default 200kb/s-r fps sets frame rate default 25-s size sets frame size format to WXH default 160X128. The following abbreviations can also be used directly: Sqcif 128X96 qcif 176X144 cif 252X288 4cif 704X576-aspect aspect sets the aspect ratio 4:3 16:9 or 1.3333 1.7777-croptop size sets the top excision band size pixel unit-cropbottom size-cropleft size-cropright size-padtop size sets the top completion pixel unit-padbottom size-padleft size-padright size-padcolor color sets the complement bar color (number of hex,6 hexadecimal, red: green: blue arrangement For example, 000000 means black)-vn does not record video-bt tolerance sets video bitrate tolerance kbit/s-maxrate bitrate sets maximum video bitrate tolerance-minrate bitreate sets minimum video bitrate tolerance-bufsize size sets rate control buffer size-vcodec codec forces the use of codec codec. If copy is used to indicate that the original codec data must be copied. -sameq uses the same video quality as the source (VBR)-pass n selects the number of processing times (1 or 2). Coding twice is very useful. Generate statistics for the first time The second pass generates an accurate requested bitrate-passlogfile file selects a recording file named file-c) Advanced Video option-g gop_size sets the image group size-intra is only suitable for intra coding-qscale Q uses fixed video quantization scale (VBR)-qmin Q minimum video quantization scale (VBR)-qmax Q maximum video quantization scale (VBR)-maximum between qdiff Q quantization scales Deviation (VBR)-qblur blur video quantization scaling softening (VBR)-qcomp compression video quantization scaling compression (VBR)-initial complexity of rc_init_cplx complexity pass coding-qp factor of b_qfactor factor between p and b frames-qp factor of i_qfactor factor between p and I frames-qp deviation of b_qoffset offset between p and b frames-qp deviation of i_qoffset offset between p and I frames- Rc_eq equation setting rate control equation default me method ^ qComp-rc_override override rate control overload-me method setting motion estimation methods are zero phods log x1 epzs (default) full-dct_algo algo setting dct algorithm available 0 FF_DCT_AUTO default DCT 1 FF_DCT_FASTINT 2 FF_DCT_INT 3 FF_DCT_MMX 4 FF_DCT_MLIB 5 FF_DCT_ALTIVEC-idct_algo algo set idct algorithm. Available 0 FF_IDCT_AUTO default IDCT 1 FF_IDCT_INT 2 FF_IDCT_SIMPLE 3 FF_IDCT_SIMPLEMMX 4 FF_IDCT_LIBMPEG2MMX 5 FF_IDCT_PS2 6 FF_IDCT_MLIB 7 FF_IDCT_ARM 8 FF_IDCT_ALTIVEC 9 FF_IDCT_SH4 10 FF_IDCT_SIMPLEARM-er n setting error residue n 1 FF_ER_CAREFULL default 2 FF_ER_COMPLIANT 3 FF_ER_AGGRESSIVE 4 FF_ER_VERY_AGGRESSIVE-ec bit_mask setting error masking to bit_mask The value is as follows: bitmask 1 FF_EC_GUESS_MVS (default=enabled) 2 FF_EC_DEBLOCK (default=enabled)-bf frames uses frames B frames Support for mpeg1,mpeg2 Mpeg4-mbd mode macroblock decision 0 FF_MB_DECISION_SIMPLE uses mb_cmp 1 FF_MB_DECISION_BITS 2 FF_MB_DECISION_RD-4mv uses 4 motion vectors only for mpeg4-part use data partition only for mpeg4-bug param bypass problems not automatically detected to encoder-strict strictness and standard rigor-aic enables advanced intra coding h363c +-umv enables infinite motion vectors h363c-deinterlace No interleaving method-interlace forced interleaving coding is only effective for mpeg2 and mpeg4. Use this option when your input is interlaced and you want to keep interleaving to minimize image loss. The optional method is not interleaving, but the loss is greater-psnr calculates psnr-vstats output video coding statistics of compressed frames to vstats_hhmmss.log-vhook module insert video processing module module includes module name and parameters Separate Audio options with spaces D) Audio options-ab bitrate sets audio bitrate-ar freq sets audio sampling rate-ac channels setting channel defaults to 1-an does not enable audio recording-acodec codec uses codec codec E) Audio / video capture options-vd device sets video capture device. For example, / dev/video0-vc channel sets video capture channel DV1394 specific-tvstd standard sets TV standard NTSC PAL (SECAM)-dv1394 sets DV1394 capture-av device sets audio devices such as / dev/dsp F) Advanced options-map file:stream sets input stream mapping-debug prints specific debugging information-benchmark adds time for benchmarking-hex dumps every input package-bitexact uses only bits Precise algorithm for codec testing-ps size sets packet size In bits-re reads data at local frame frequency and is mainly used to simulate the capture device-loop cyclic input stream. Works only on image streams for ffserver testing

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