Am 20.02.2020 um 12:49 schrieb Paul B Mahol:
On 2/20/20, Michael Koch <[email protected]> wrote:
Am 20.02.2020 um 11:07 schrieb Paul B Mahol:
On 2/20/20, Michael Koch <[email protected]> wrote:
I'd like to understand how the new "fill" option in the remap filter
works.
What is an "unmapped pixel"? How is it possible that pixels are
unmapped, if the xmap and ymap files have the same size as the output
image? Is a pixel "unmapped" if it has invalid coordinates (negative or
too big) in the xmap or ymap files?
Previously all unmapped pixels were set to black for rgba or dark
green for y420p.
It is very obvious to understand even for every little kid in the block.
Finally I got it working. A pixel can be declared as "unmapped" by
setting the values to 65535 in the xmap and ymap files. However using a
negative value (for example -1) doesn't work. In this case the pixel is
mapped to the top left pixel of the input image.
This behaviour might be obvious for little kids, but not for me. Should
be added to documentation.
Nope. Documentation does not need trivial information.
Obviously by having even limited programming experience one would
found out that remaps are unsigned short, thus can not be negative.
You never showed your map files. so I assume everything is wrong on
your end.
This is an example that produces a crash abort in the third command
line. All pixels are mapped to themselves, except pixel (1,1) which is
mapped to (65535,65535)
c:\ffmpeg\ffmpeg -f lavfi -i nullsrc=size=20x20 -vf
format=pix_fmts=gray16le,geq='if(bitand(eq(X,1),eq(Y,1)),65535,X)'
-frames 1 -y xmap.pgm
c:\ffmpeg\ffmpeg -f lavfi -i nullsrc=size=20x20 -vf
format=pix_fmts=gray16le,geq='if(bitand(eq(X,1),eq(Y,1)),65535,Y)'
-frames 1 -y ymap.pgm
c:\ffmpeg\ffmpeg -f lavfi -i color=blue:size=20x20 -i xmap.pgm -i
ymap.pgm -lavfi "format=pix_fmts=rgb24,remap=fill=red" -frames 1 -y out.png
Console output for third command line:
F:\Wormhole_2020>c:\ffmpeg\ffmpeg -f lavfi -i color=blue:size=20x20 -i
xmap.pgm
-i ymap.pgm -lavfi "format=pix_fmts=rgb24,remap=fill=red" -frames 1 -y
out.png
ffmpeg version git-2020-02-18-ebee808 Copyright (c) 2000-2020 the FFmpeg
develop
ers
built with gcc 9.2.1 (GCC) 20200122
configuration: --enable-gpl --enable-version3 --enable-sdl2
--enable-fontconfi
g --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d
--enable-libb
luray --enable-libfreetype --enable-libmp3lame
--enable-libopencore-amrnb --enab
le-libopencore-amrwb --enable-libopenjpeg --enable-libopus
--enable-libshine --e
nable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame
--enable
-libvpx --enable-libwavpack --enable-libwebp --enable-libx264
--enable-libx265 -
-enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib
--enable-gmp --enab
le-libvidstab --enable-libvorbis --enable-libvo-amrwbenc
--enable-libmysofa --en
able-libspeex --enable-libxvid --enable-libaom --enable-libmfx
--enable-ffnvcode
c --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec
--enable-dxva2 -
-enable-avisynth --enable-libopenmpt --enable-amf
libavutil 56. 41.100 / 56. 41.100
libavcodec 58. 70.100 / 58. 70.100
libavformat 58. 38.101 / 58. 38.101
libavdevice 58. 9.103 / 58. 9.103
libavfilter 7. 76.100 / 7. 76.100
libswscale 5. 6.100 / 5. 6.100
libswresample 3. 6.100 / 3. 6.100
libpostproc 55. 6.100 / 55. 6.100
Input #0, lavfi, from 'color=blue:size=20x20':
Duration: N/A, start: 0.000000, bitrate: N/A
Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 20x20
[SAR 1:1 DA
R 1:1], 25 tbr, 25 tbn, 25 tbc
Input #1, pgm_pipe, from 'xmap.pgm':
Duration: N/A, bitrate: N/A
Stream #1:0: Video: pgm, gray16le, 20x20, 25 tbr, 25 tbn, 25 tbc
Input #2, pgm_pipe, from 'ymap.pgm':
Duration: N/A, bitrate: N/A
Stream #2:0: Video: pgm, gray16le, 20x20, 25 tbr, 25 tbn, 25 tbc
Stream mapping:
Stream #0:0 (rawvideo) -> format
Stream #1:0 (pgm) -> remap:xmap
Stream #2:0 (pgm) -> remap:ymap
remap -> Stream #0:0 (png)
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