Prefix code decoding seems to work fairly well and produces a ton of
log output with `#define WEBP_DEBUG 1`, so remove the log lines.
(If needed it's always possible to just locally revert this commit.)
No behavior change, since WEBP_DEBUG isn't usually defined.
WebP lossless files that use a color indexing transform with <= 16
colors use pixel bundling to pack 2, 4, or 8 pixels into a single pixel.
If the image's width doesn't happen to be an exact multiple of the
bundling factor, we need to:
1. Use ceil_div() instead of just dividing the width by the bundling
factor
2. Remember the original width and use it instead of computing
reduced width times bundling factor
This does these changes, and adds a simple test for it -- it at least
checks that the decoded images have the right size.
(I created these images myself in Photoshop, and used the same
technique as for Tests/LibGfx/test-inputs/catdog-alert-*.webp
to create images with a certain number of colors.)
If the video element has a 'controls' attribute, we now paint some basic
video controls over the video element. If no frame has been decoded yet,
we paint a play button on the center of the element.
If a frame has been decoded, we paint that frame and paint a control bar
on the bottom of the frame. This control bar currently only contains a
play/pause button, depending on the video's playback state. We will only
paint the control bar if the video is paused or hovered.
Note that the default value of the attribute is true. We were previously
autoplaying videos as soon as they loaded - this will prevent that from
happening until the paused attribute is set to false.
See the lengthy comment added in this commit for details.
With this, the webp lossless decoder is feature complete :^)
(...except for bug fixes and performance improvements, as always.)
...in addition to modifying in-place. This is needed for bitpacking
support for the color indexing transform (and it could also be used
to make the color indexing transform return an indexed bitmap, which
is something we could do if that's the last transform that's applied).
No behavior change.
Reduces the time to run
Build/lagom/image ~/src/libwebp/webp_js/test_webp_wasm.webp -o tmp.png
from 0.5s to 0.25s.
Before, 60% of the time was spent decoding webp and 40% writing png.
Now, 16% of the time was spent decoding webp and 84% writing png.
That means png writing takes 0.2s, and webp decoding time went from
0.3s to 0.05s.
A template expression without explicit return type deduces its return
type as if for a function whose return type is declared auto. That
does deduce return-by-value, while `decltype(auto)` would deduce
return-by-reference. Explictly saying `decltype(auto)` would work
too, but writing out the type is maybe easier to understand.
No behavior change other than being much faster.
The previous attempt was in commit e5e9d3b877, where I thought
max_symbol describes how many code lengths should be read.
But it looks like it instead describes how many code length input
symbols should be read. (The two aren't the same since one code length
input symbol can produce several code lengths.)
I still agree with the commit description of e5e9d3b877 that the spec
isn't very clear on this :)
This time I've found a file that sets max_symbol and with this change
here, that file decodes correctly. (It's Qpalette.webp, which I'm about
to add as a test case.)
This ports MouseEvent, UIEvent, WheelEvent, and Event to new String.
They all had a dependency to T::create() in
WebDriverConnection::fire_an_event() and therefore had to be ported in
the same commit.
Webp lossless can have up to 2328 symbols. This code assumed the deflate
max of 288, leading to crashes for webp lossless files using more than
288 symbols (such as Tests/LibGfx/test-inputs/simple-vp8l.webp).
Nothing writes webp files at this point, so the m_bit_codes and
m_bit_code_lengths arrays aren't ever used in practice with more than
288 entries.
WebP lossless differs from deflate in how it handles 1-element codes.
Deflate consumes one bit from the bitstream to produce the element,
while webp lossless consumes 0 bits. Add a wrapper class to handle
this case.
It's not totally clear to me when all of these states are supposed to be
set. For example, nothing in the HTMLMediaElement spec says to "set the
readyState attribute to HAVE_ENOUGH_DATA". However, this will at least
advance the readyState to HAVE_METADATA, which is needed for other
useful attributes for debugging.
The spec for loading a media element is quite huge. This implements just
enough to parse the attribute, fetch the corresponding media object, and
decode the media object (if it is a video). While doing so, this also
implements most network state tracking and firing DOM events that may be
observed via JavaScript.
Some elements, like HTMLMediaElement, must have a unique task sources
for every instance of that element that is created. Support this with a
simple wrapper around IDAllocator.
This copies the video data from the Matroska document into the Track
structure that outside users have access to. Because Track can actually
represent other media types, this is set up such that the Track can hold
metadata for those other types when they are needed.
This is needed for LibWeb's HTMLMediaElement implementation.
