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#994 Cannot replace alpha channel
Author: user laforet
Date created:
Type: bug
Visibility: Everybody
Assigned to:
State: closed Help

> What steps will reproduce the problem? Open any swf file with JPEG3 tags, attempt to replace the alpha channel from either the GUI or CLI > What is the expected output? What do you see instead? GUI: Trying to load alpha masks in PNG or BMP format results in an error message "Invalid image". There is no indication of which file types can be used in the file browser window.I did look up but there is no documentation on this feature. Did I use it the way it was designed to work? CLI: I tried to following the format in the help output and it only returns "I/O error during reading" > What version of the product are you using? Is it "nightly build"? Which operating system do you have? 6.0.1 stable and nightly 779 on Windows Vista x64.
Error message fixed:) Now it shows "Invalid alpha channel data". It is not an image file, it is only a binary file. The filesize should be equal to the count of the pixels. Each byte means the alpha value of the corresponding pixel. The file is not compressed. So when all the pixels are fully visible, the file should contain 0xff characters only.
State: new→upgraded
See the swf specification: Page 139. The only difference that the ZLIB compression is done internally by FFDec.
Thank you, that makes for sense. I was a bit confused when you mentioned alpha.bin earlier in #985 I will have an attempt at generating the correct binary format. You can close this issue for now :)
State: upgraded→closed