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• avutil : add ROI (Region Of Interest) data struct and bump version

  10 janvier 2019, par Guo, Yejun

  avutil : add ROI (Region Of Interest) data struct and bump version
  The encoders such as libx264 support different QPs offset for different MBs,
  
  it makes possible for ROI-based encoding. It makes sense to add support
  
  within ffmpeg to generate/accept ROI infos and pass into encoders.
  Typical usage : After AVFrame is decoded, a ffmpeg filter or user's code
  
  generates ROI info for that frame, and the encoder finally does the
  
  ROI-based encoding.
  The ROI info is maintained as side data of AVFrame.
  Signed-off-by : Guo, Yejun <yejun.guo@intel.com>
  
  Signed-off-by : Derek Buitenhuis <derek.buitenhuis@gmail.com>
  

  • [DH] doc/APIchanges
  • [DH] libavutil/frame.c
  • [DH] libavutil/frame.h
  • [DH] libavutil/version.h

• moviepy black border around png when compositing into an MP4

  27 août 2022, par OneWorld

  compositing a png into an MP4 video creates a black border around the edge.

  


  This is using moviepy 1.0.0

  


  Code below reproduces the MP4 with the attached red text png.

  


  

  


  import numpy as np
import moviepy.editor as mped
def composite_txtpng_on_colour():
    bg_color = mped.ColorClip(size=[400, 300], color=np.array([0, 255, 0]).astype(np.uint8),
                          duration=2).set_position((0, 0))
    text_png_postition = [5, 5]
    text_png = mped.ImageClip("./txtpng.png", duration=3).set_position((text_png_postition))

    canvas_size = bg_color.size
    stacked_clips = mped.CompositeVideoClip([bg_color, text_png], size=canvas_size).set_duration(2)
    stacked_clips.write_videofile('text_with_black_border_video.mp4', fps=24)

composite_txtpng_on_colour()


  


  The result is an MP4 that can be played in VLC player. A screenshot of the black edge can be seen below :-

  


  

  


  Any suggestions to remove the black borders would be much appreciated.

  


  Update : It looks like moviepy does a blit instead of alpha compositing.

  


  def blit(im1, im2, pos=None, mask=None, ismask=False):
    """ Blit an image over another.  Blits ``im1`` on ``im2`` as position ``pos=(x,y)``, using the
    ``mask`` if provided. If ``im1`` and ``im2`` are mask pictures
    (2D float arrays) then ``ismask`` must be ``True``.
    """
    if pos is None:
        pos = [0, 0]

    # xp1,yp1,xp2,yp2 = blit area on im2
    # x1,y1,x2,y2 = area of im1 to blit on im2
    xp, yp = pos
    x1 = max(0, -xp)
    y1 = max(0, -yp)
    h1, w1 = im1.shape[:2]
    h2, w2 = im2.shape[:2]
    xp2 = min(w2, xp + w1)
    yp2 = min(h2, yp + h1)
    x2 = min(w1, w2 - xp)
    y2 = min(h1, h2 - yp)
    xp1 = max(0, xp)
    yp1 = max(0, yp)

    if (xp1 >= xp2) or (yp1 >= yp2):
        return im2

    blitted = im1[y1:y2, x1:x2]

    new_im2 = +im2

    if mask is None:
        new_im2[yp1:yp2, xp1:xp2] = blitted
    else:
        mask = mask[y1:y2, x1:x2]
        if len(im1.shape) == 3:
            mask = np.dstack(3 * [mask])
        blit_region = new_im2[yp1:yp2, xp1:xp2]
        new_im2[yp1:yp2, xp1:xp2] = (1.0 * mask * blitted + (1.0 - mask) * blit_region)
    
    return new_im2.astype('uint8') if (not ismask) else new_im2


  


  and so, Rotem is right.

  


  new_im2[yp1:yp2, xp1:xp2] = (1.0 * mask * blitted + (1.0 - mask) * blit_region)


  


  is

  


  (alpha * img_rgb + (1.0 - alpha) * bg)


  


  and this is how moviepy composites. And this is why we see black at the edges.

  


• In FFmpeg, using -filter_complex, how can I overlay and blend at the same time ?

  20 avril 2023, par Kristian Boruff

  My code works to combine three videos, resize the videos to 1920X1080, resize the watermark to the correct size, and then overlays the watermark to the lower left hand side. Then converts to the intended codecs for Youtube.
My question is how do I Blend at the same time using the -filter_complex workflow ?
Currently, I have the following workflow that does everything but set the opacity

  



  ffmpeg -y -i fancy movie.mov -i logo.png -i in.mov -i out.mov -c:v libx264 -crf 18 -b:v 50000k -preset veryfast -tune film -profile:v high -x264opts cabac=1:keyint=16:bframes=2:keyint_min=15 -c:a libvo_aacenc -ab 128K -ar 48000 -filter_complex "[0:0] scale=1920X1080 [main]; [2:0] scale=1920X1080 [start]; [3:0] scale=1920X1080 [end]; [start] [2:1] [main] [0:1] [end] [3:1] concat=n=3:v=1:a=1 [prog]; [1:0] scale=480:90 [wm]; [prog] [wm] overlay=36:main_h-overlay_h-45" fart.mp4


  



  I'm trying to add "blend=all_opacity=0.7" in the last step so the watermark will screen against the background. If I just add

  



  [prog] [wm] overlay=36:main_h-overlay_h-45, blend=all_mode='overlay':all_opacity=0.7" fart.mp4


  



  I get the error, Cannot find a matching stream for unlabeled input pad 1 on filter Parsed_blend_6

  



  If I try a semicolon instead,

  



  [prog] [wm] overlay=36:main_h-overlay_h-45; blend=all_mode='overlay':all_opacity=0.7


  



  I get the error, Cannot find a matching stream for unlabeled input pad 0 on filter Parsed_blend_6 which makes me think that it's expecting something like [input 1] [input 2] blend command [output]. The problem is that I need it to overlay and blend.

  



  I tried simplifying the code to just test if the blend operation was working properly.

  



  ffmpeg -i test.mp4 -i logo.png -filter_complex "[0:0] scale=1920x1080 [wm]; [1:0] scale=1920x1080 [prog], [wm][prog] blend=all_mode='overlay':all_opacity=0.7" fart.mp4


  



  I got the error First input link top parameters (size 1920x1080, SAR 1:1) do not match the corresponding second input link bottom parameters (1920x1080, SAR 243:80)
Failed to configure output pad on Parsed_blend_2

  



  So, in addition to the trouble with combining of filters, I'm also having an issue with resizing the watermark as FFMpeg sees it as a different aspect ratio than the other videos.

  



  This is my second day with FFmpeg, so any help would be appreciated.

  



  I'm currently working with FFMpeg version N-61061-gf34cceb