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• FFMPEG : Creating video using drawtext along with word wrap and padding

  11 octobre 2022, par Chaitanya Sai

  I'm working to create a video from text with drawtext filter. Output video i can see the text is overflowing instead of coming in new line.

  



  Is there any way i can archive word wrapping and also set the internal padding to video ?

  



  Below is the snippet I'm using to generate video from text

  



  ffmpeg.exe -f lavfi -i color=c=white:s=640x480:d=5.396 -vf "[in] drawtext=fontfile=font.ttf:fontsize=20:fontcolor=black:x=0+0*print(tw):y=0+0*print(th):text='this is new whiteboard te':enable='between(t,6.634,6.818)',drawtext=fontfile=font.ttf:fontsize=20:fontcolor=black:x=0+0*print(tw):y=0+0*print(th):text='this is new whiteboard testing':enable='between(t,0.0,2.032)',drawtext=fontfile=font.ttf:fontsize=20:fontcolor=black:x=0+0*print(tw):y=0+0*print(th):text='this is new whiteboard testing no padding and the text is overflowing from the video frame check this  need to acheve word wrapping':enable='between(t,2.032,5.396)'"[out] -c:v libx264 -t 30 -crf 30 ../output.mp4


  



  Output looks like this


  


• What does the word "context" usually mean in structures ?

  8 juin 2015, par ArturPhilibin

  I’m trying to build an application using some of ffmpeg’s libraries and I’m noticing many data structures with the word "Context" in them.

  You can see some here http://www.ffmpeg.org/doxygen/trunk/classes.html

  I don’t understand the use of the word "context" in this.. context.

  Any hints as to what it generally means ?

• Missing piece between libjpeg-turbo & h264 ffmpeg C/C++

  15 octobre 2022, par Nelstaar

  On the left side I have a buffer with decoded pixels that I can get in two formats :

  


  RGB interleaved/packed where bytes in buffer are R0G0B0R1G1B1....

  


  or

  


  YUV444 interleaved/packed where bytes in buffer are Y0U0V0Y1U1V1...

  


  (JCS_RGB or JCS_YCbCr in jpeglib.h)

  


  (Please note that I use libjpeg-turbo because I need to decompress a cropped region of the image. (jpeg_crop_scanline()))

  


  On the right side I have x264 codec via ffmpeg that support only planar pixel formats :

  


  yuv420p, yuvj420p, yuv422p, yuvj422p, yuv444p, yuvj444p, nv12, nv16, nv21, yuv420p10le, yuv422p10le, yuv444p10le, nv20le

  


  yuv444p where bytes in buffer are Y0Y1Y2...U0U1...V0V1...

  


  according to ffmpeg -h encoder=libx264

  


  I have some ideas already :

  


  

  • Decompress Jpeg to RBG888 in buffer 1 then libswscale to yuv420p in buffer 2 and encoding. (copy)

  


  • Decompress Jpeg to YUV444 interleaved in buffer 1 then SSSE3 magic in buffer 1 to yuv444p and encoding. (no copy)

  


  • or else.

  


  


  What would be the most effective fastest way ?

  


  I which to avoid buffer copy.

  


  Movie have the same width & height than Jpegs.