As pointed out in commit ed01df, the quality loss due to frequent
conversion between RGB and YUV is too much when drawing OSD and
subtitles.
Fix this by staying in the same colorspace when drawing subtitles.
Render directly to RGB, without converting to YUV first.
The bad thing about packed RGB is that there are many pixel formats,
which would all require special code for blending. It's also completely
incompatible to planar YUV. Use planar RGB instead, which allows us to
reuse all code originally written for planar YUV. The only thing that
needs to be changed is the color conversion in the libass case. (In
exchange for simpler code, the image has to be copied, but this is
still much better than converting to YUV.)
Unfortunately, libswscale doesn't support planar RGB output. Add a hack
to sws_utils.c to handle conversion to planar RGB. In the common case,
when converting 32 bit per pixel RGB, calling swscale can be avoided
entirely.
The change in mp_image.c is needed to allocate GBRP images correctly.
(The issue with vo_x11 could be easily solved by always backing up the
same bounding box as the bitmap drawing RGB<->YUV conversion does, but
this commit is probably the better fix.)
In order to improve performance, vo_xv didn't create a backup of the
video frame before drawing OSD and subtitles during normal playback. It
required the frontend to do frame stepping if it wanted to redraw the
OSD, but no backup of the video frame was available. (Consider the
following use case: enable the OSD permanently with --osd-level=3, then
pause during playback and do something that shows an OSD message. The
player will advance the video by one frame at the time the new OSD
message is first drawn.)
This also meant that taking a screenshot during playback with vo_xv
would include OSD and subtitles in the resulting image.
Fix this by always creating a backup before drawing OSD or subtitles.
In order to avoid having to create a full copy of the whole image frame,
introduce a complex scheme that tries to backup only the changed
regions.
It's unclear whether the additional complexity in draw_bmp.c for
backing up only the changed areas of the frame is worth it. Possibly
a simpler implementation would suffice, such as tracking only Y ranges
of changed image data, or even just copying the full frame.
vo_xv's get_screenshot() now always creates a copy in order not to
modify the currently displayed frame.
Finish renaming directories and moving files. Adjust all include
statements to make the previous commit compile.
The two commits are separate, because git is bad at tracking renames
and content changes at the same time.
Also take this as an opportunity to remove the separation between
"common" and "mplayer" sources in the Makefile. ("common" used to be
shared between mplayer and mencoder.)
Mostly pedantic bikeshedding issues.
Move some code around, so that the sub_bitmap_to_mp_images() function
can be split into two parts. This is better than having a big function
with many input and outputs, of which only half are used in each code
path.
Also, try to make code simpler by using a mp_rect type.
Most of these cased working when the OSD was switched to libass, or
didn't do anything even before that.
Also don't recursively include subreader.h in sub.h.
libswscale tends to overwrite the area between (w,y)-(0,y+1). It tries
to process multiple pixels at once, and if the memory past the last x
pixel is inside a SIMD operation, but still below the image stride, it
overwrites that data with black.
This happens with vo_x11 and 32 bit RGBA formats. The bug is visible as
black bar right of the subtitle bounding box. Fix by giving libswscale
more alignment. Then the "outside" pixels are inside, and are processed
normally instead of overwritten with black.
NOTE: we do not increase the alignment constant, because this is a
separate issue from pointer alignment. libavutil's av_malloc() wouldn't
actually satisfy the increased alignment either.