Doing "mpv --vo=opengl:lscale=help" now lists possible scalers and
exits. The "backend" suboption behaves similar. Make the "stereo"
suboption a choice, instead of using magic integer values.
Until now, only formats directly supported by OpenGL were supported.
This excludes various permutations of 8-bit RGB[A|0]. But we can simply
permutate the color channels in the shader, so do that. This also adds
support for all these weird RGB0 formats.
Note that we could use libavutil's pixfmt list instead of the
mp_packed_formats array, but trying to decrypt the pixfmt info would
probably end in pain, so this array with duplicated information is
actually better and shorter.
Note: I didn't actually test whether the alpha components are reproduced
correctly with alpha formats.
Use the video decoder chroma location flags and render chroma locations
other than centered. Until now, we've always used the intuitive and
obvious centered chroma location, but H.264 uses something else.
FFmpeg provides a small overview in libavcodec/avcodec.h:
-----------
/**
* X X 3 4 X X are luma samples,
* 1 2 1-6 are possible chroma positions
* X X 5 6 X 0 is undefined/unknown position
*/
enum AVChromaLocation{
AVCHROMA_LOC_UNSPECIFIED = 0,
AVCHROMA_LOC_LEFT = 1, ///< mpeg2/4, h264 default
AVCHROMA_LOC_CENTER = 2, ///< mpeg1, jpeg, h263
AVCHROMA_LOC_TOPLEFT = 3, ///< DV
AVCHROMA_LOC_TOP = 4,
AVCHROMA_LOC_BOTTOMLEFT = 5,
AVCHROMA_LOC_BOTTOM = 6,
AVCHROMA_LOC_NB , ///< Not part of ABI
};
-----------
The visual difference is literally minimal, but since videophiles
apparently consider this detail as quality mark of a video renderer,
support it anyway. We don't bother with chroma locations other than
centered and left, though.
Not sure about correctness, but it's probably ok.
The filter chain and the video ouputs have config() functions. They are
strictly limited to transfering the video size and format. Other
parameters (like color levels) have to be transferred separately.
Improve upon this by introducing a separate set of reconfig() functions,
which use mp_image_params to carry format parameters. This struct
contains all image format related parameters from config(), plus
additional parameters such as colorspace.
Change vf_rotate to use it, as well as vo_opengl. vf_rotate is just
an example/test case, but vo_opengl will need it later.
The intention is also to get rid of VOCTRL_SET_YUV_COLORSPACE. This
information is now handed to the VOs via reconfig(). The getter,
VOCTRL_GET_YUV_COLORSPACE, will still be needed though.
When the displayed image is cropped in Y direction (like using panscan
controls when playing 4:3 video on a 16:9 monitor), and separated
scaling is used, the texture size for the FBO holding the intermediate
result was calculated incorrectly. This could lead to artifacts, which
were quite apparent with extreme scale factors.
Actually, the size of that texture is OK, but the texture shouldn't be
used to hold the complete scaled image. Instead, it should be used for
the visible part of the image only. Because separate scaling works by
scaling in Y direction first, it's still fine to scale the image on the
full image width on the first pass. This helps avoiding artifacts on
the left/right border of the image when scaling in X direction, as the
scaler will try to fetch pixels from beyond the border. (The left border
is still kind of fine, but the right border will fetch garbage, unless
the texture is strictly sized, or explicit clamping is added to the
shader. Too much trouble, so using the full image width is simpler.)
Also fix some issues with no-npot mode, which enables use of power-of-2
textures. Maybe this mode isn't really useful anymore (modern hardware
is faster with smaller non-power-of-2 textures), but keep it for now.
Originally, the header wasn't supposed to contain random compatibility
stuff, but now all that is printed with -v. Add a hack to skip it and
to reduce the noise.
This probes and prints the depth of some texture formats with the help
of a FBO. By default it tests the format used for scaling, as well as
the format used for dithering and the 3D LUT (if any of these are
enabled).
The output is visible only with -v. Some representative values are
probed, and the difference of input and output value is printed as hex-
float. Hex-floats are used because they make the implied precision more
obvious. Originally I wanted to do some more sophisticated guessing of
the implied depth/precision for more user-friendly reporting, but then
I decided that printing raw data is better for debugging, especially if
things go wrong.
This does not try to disable any functionality and does not print any
warnings if the depth is lower than what it should be.
The internal texture format GL_RED is typically 8 bit, which is clearly
not good enough for the new dither matrix. The idea was to use a float
texture format, but this was somehow "forgotten". Use GL_R16, since
16 bit textures are more robust, and provide more precision for the
same memory usage.
Change how the offset for centering the dither matrix is applied. This
is needed for making it possible to round up values to the target depth.
Before this commit, this changed the output even if the input was exact
and input and output depth were the same, which is not really what you
want. Now it doesn't do that anymore.
Use a different algorithm to generate the dithering matrix. This
looks much better than the previous ordered dither matrix with its
cross-hatch artifacts.
The matrix generation algorithm as well as its implementation was
contributed by Wessel Dankers aka Fruit. The code in dither.c is
his implementation, reformatted and with static global variables
removed by me.
The new matrix is uploaded as float texture - before this commit, it
was a normal integer fixed point matrix. This means dithering will
be disabled on systems without float textures.
The size of the dithering matrix can be configured, as the matrix is
generated at runtime. The generation of the matrix can take rather
long, and is already unacceptable with size 8. The default is at 6,
which takes about 100 ms on a Core2 Duo system with dither.c compiled
at -O2, which I consider just about acceptable.
The old ordered dithering is still available and can be selected by
putting the dither=ordered sub-option. The ordered dither matrix
generation code was moved to dither.c. This function was originally
written by Uoti Urpala.
gl_video_resize_redraw() simply resizes and redraws (but without
invoking swapGlBuffers()). The VO is not involved in any way, so this
can simply be called from inside the mpgl lock from any thread.
Requires a minor refactor of the GL OSD code in order to redraw without
an OSD object.
Useful for the j2k decoder.
Matrix taken from http://www.brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html
(XYZ to sRGB, whitepoint D65)
Gamma conversion follows what libswscale does (2.6 in, 2.2 out).
If linear RGB is used internally for scaling, the gamma conversion
will be undone by setting the exponent to 1. Unfortunately, the two
gamma values don't compensate each others exactly (2.2 vs. 1/0.45=2.22...),
so output is a little bit incorrect in sRGB or color-managed mode. But
for now try hard to match libswscale output, which may or may not be
correct.
The previous attempt was missing some code paths, so there were still
shaders generated that triggered the shader compilation error. Fix it
instead by special handling USE_CONV in the shader.
By the way, the shader compiler did not accept:
#if defined(USE_CONV) && (USE_CONV == ...)
In my opinion this should be perfectly fine, but it gives the same
error as before. So test USE_CONV separately with #ifndef.
The OSX shader compiler was giving this error:
ERROR: 0:235: '' : syntax error incorrect preprocessor directive
on this line:
[235] #if USE_CONV == CONV_PLANAR
USE_CONV was undefined in some cases. The expected behavior is that the
shader preprocessor interprets this as branch not taken (AFAIK exactly
as in C), which is probably what the standard would dictate. This is
possible an OSX bug. But admittedly, I'm not sure whether this is really
standard behavior (in C or GLSL), and doing this is extremely weird at
best, so make sure that USE_CONV is always defined.
Should fix behavior on OSX.
Allows playing video with alpha information on X11, as long as the video
contains alpha and the window manager does compositing. See vo.rst.
Whether a window can be transparent is decided by the choice of the X
Visual used for window creation. Unfortunately, there's no direct way to
request such a Visual through the GLX or the X API, and use of the
XRender extension is required to find out whether a Visual implies a
framebuffer with alpha used by XRender (see for example [1]). Instead of
depending on the XRender wrapper library (which would require annoying
configure checks, even though XRender is virtually always supported),
use a simple heuristics to find out whether a Visual has alpha. Since
getting it wrong just means an optional feature will not work as
expected, we consider this ok.
[1] http://stackoverflow.com/questions/4052940/how-to-make-an-opengl-rendering-context-with-transparent-background/9215724#9215724
When displaying YUV with alpha plane (an extremely rare special case),
we didn't upload the alpha plane, because we don't do anything with it.
This actually created some annoying special cases, so upload the alpha
planes as well, even if they're unused.
This is a bit cleaner. Also don't repeat the chroma shift calculations
over and over, but store the image size instead, which is simpler and
will give us a chance to fix display of non-mod-2 image sizes.
gl_video.c contains all rendering code, gl_lcms.c the .icc loader and
creation of 3D LUT (and all LittleCMS specific code). vo_opengl.c is
reduced to interfacing between the various parts.
wm4
Martin Herkt
Stefano Pigozzi