LibGfx: Add APNG Writing Support to PNGWriter #24021
Conversation
github-actions
bot
added
the
👀 pr-needs-review
OfficialPixelBrush
changed the title
OfficialPixelBrush
force-pushed
the
apng-writing
branch
from
b2e88ea
to
120aa3d
Compare
There was a problem hiding this comment.
I'm not a graphics person so I'll let @nico or @LucasChollet weigh in on that. Generally it seems good. You do need to run clang-format on your changes though, that's what CI is complaining about.
OfficialPixelBrush
force-pushed
the
apng-writing
branch
3 times, most recently
from
566cd6a
to
4ddcf0a
Compare
There was a problem hiding this comment.
Seems generally alright. Might be nice to include a test.
For the "screen recording" use case, it'd probably nice to have an API that streams the images instead of having to assemble them all into a big vector.
Also, maybe it makes sense to put this in the PR that adds a call to the new function? As is, this is adding a dead function. (Not the end of the world if its caller comes soon after.)
| dbgln("frame #{}", sequence_number); | ||
| TRY(writer.add_fcTL_chunk(sequence_number, b.width(), b.height(), delay_num, delay_den, dispose_op, blend_op)); | ||
| sequence_number++; | ||
| TRY(writer.add_IDAT_chunk(b, true, sequence_number)); |
There was a problem hiding this comment.
This is writing bitmap[0] a second time. Is that intentional?
There was a problem hiding this comment.
APNG accepts two formats. In this, the thumbnail is separate from the first frame. In the other, it's the same as the first frame. I was originally going to allow the submission of a separate thumbnail image, but this probably has little purpose in this context. I might rework it a bit.
| @@ -281,4 +322,26 @@ ErrorOr<ByteBuffer> PNGWriter::encode(Gfx::Bitmap const& bitmap, Options options | |||
| return ByteBuffer::copy(writer.m_data); | |||
| } | |||
|
|
|||
| ErrorOr<ByteBuffer> PNGWriter::encodeAnimated(AK::Vector<Gfx::Bitmap const&> bitmap, u16 delay_num = 1, u16 delay_den = 30, u8 dispose_op = 0, u8 blend_op = 0, Options options) | |||
There was a problem hiding this comment.
serenity style is encode_animated
|
Good point. Depends on how I do it. The APNG could be created somewhere, then appended onto with each frame. Right now, I'm not really sure where I could use the function, outside of the extension of shot I've begun to develop that allows recording of APNGs. |
|
I guess this can be used in pixel paint but that might require some work as I don't think we support animated images there. |
|
I was thinking this'd be a great opportunity for someone to add basic animation capabilities to PixelPaint. Will need to look into |
|
This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. Thank you for your contributions! |
|
We now have an |
OfficialPixelBrush
force-pushed
the
apng-writing
branch
2 times, most recently
from
f3f7daa
to
3d861e6
Compare
OfficialPixelBrush
force-pushed
the
apng-writing
branch
from
3d861e6
to
544e8b2
Compare
|
|
||
| // Let's get rid of the previously written trailer | ||
| if (!is_first_frame) | ||
| TRY(m_stream.seek(-4, SeekMode::FromEndPosition)); |
There was a problem hiding this comment.
While I still have that in mind:
Please use SeekMode::FromCurrentPosition (89aa18f)
There was a problem hiding this comment.
Cheers! Will get on that asap!
This is a relatively straight-forward commit, allowing programs to export APNG files, with a custom frame duration, blend mode, etc.
This is also my first non-image commit for SerenityOS! (Woohoo!)
To Summarize what this adds: