proposed fix for transparency issue #27173 #27406
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@JakobRing @Wuzuw do you have any interest in coming back to this PR? It seems reasonable but needs a bit of work (use |
| @@ -1079,7 +1079,11 @@ def func(current_frame: int, total_frames: int) -> Any | |||
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| def _pre_composite_to_white(color): | |||
| r, g, b, a = mcolors.to_rgba(color) | |||
| return a * np.array([r, g, b]) + 1 - a | |||
| if type(writer) == PillowWriter: | |||
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this needs to be addressed
| if type(writer) == PillowWriter: | |
| if isinstance(writer, PillowWriter): |
| @@ -1079,7 +1079,11 @@ def func(current_frame: int, total_frames: int) -> Any | |||
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| def _pre_composite_to_white(color): | |||
| r, g, b, a = mcolors.to_rgba(color) | |||
| return a * np.array([r, g, b]) + 1 - a | |||
| if type(writer) == PillowWriter: | |||
| print("no true transparency using pillow") | |||
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| print("no true transparency using pillow") |
| print("no true transparency using pillow") | ||
| return a * np.array([r, g, b]) + 1 - a | ||
| else: | ||
| return np.array([r, g, b, a]) | ||
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| savefig_kwargs['facecolor'] = _pre_composite_to_white(facecolor) |
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Given the name of the internal function _pre_composite_to_white, I think it makes more sense to put the conditional around this bit of code (and just not call the function if we don't need it) rather than make the function actually do "maybe pre-composite with white based on the type of something in my outer scope".
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Another question here is that is it better to have a "known bad" list or a "known good" list? I'm inclined to think it should be "known good" and the check should probably be more through than just the type of the writer (re-skimming the linked issues I think it depends on the encoding used not just the program). |
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We probably also need to add a keyword arguement to |
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This is superseded by #29024 . Thank you for your work @JakobRing and hopefully we will hear from you again. |
Suggestion by @Wuzuw, another friend and me for the closing of #27173
We suggest to check if the pillowwriter is used. If so we use the fix by @tacaswell in #19040 and if ffmpeg is used we use the standard rgba-values because ffmpeg can deal with transparency.