We really shouldn't be resetting duplicator state as part of gs_flush.
gs_begin_scene is not ideal because it is called twice per frame, and
only after duplicators have been ticked. Even though it makes no
user-facing difference, it makes more logical sense to reset at the top
of the frame than the bottom.
The shaders to unpack YUV information from the same texture were rather
complicated. Breaking them up into separate textures makes the shaders
much simpler, and we can remove the PRECISION_OFFSET hack.
Performance also gets a nice boost on Intel for planar textures.
Intel GPA, SetStablePowerState, Intel HD Graphics 530, 1920x1080
UYVY: 473 us -> 457 us
YUY2: 492 us -> 422 us
YVYU: 491 us -> 441 us
I420: 1637 us -> 505 us
I422: 1644 us -> 482 us
I444: 1653 us -> 504 us
NV12: 1656 us -> 369 us
Y800 (limited): 270 us -> 277 us
Y800 (full): 263 us -> 289 us
RGB (limited): 341 us -> 411 us
BGR3 (limited): 512 us -> 509 us
BGR3 (full): 527 us -> 534 us
The shaders to pack YUV information into the same texture were rather
complicated and suffering precision issues. Breaking them up into
separate textures makes the shaders much simpler and avoids having to
compute large integer offsets. Unfortunately, the code to handle
multiple textures is not as pleasant, but at least the NV12 rendering
path is no longer separate.
In addition, write chroma samples to "standard" offsets. For I444,
there's no difference, but I420/NV12 formats now have chroma shifted to
the left as 4:2:0 is shown in the H.264 specification.
Intel GPA, SetStablePowerState, Intel HD Graphics 530
Expect speed incrase:
I420: 844 us -> 493 us (254 us + 190 us + 274 us)
I444: 837 us -> 747 us (258 us + 276 us + 272 us)
NV12: 450 us -> 368 us (319 us + 168 us)
Expect no change:
NV12 (HW): 580 (481 us + 166 us) us -> 588 us (468 us + 247 us)
RGB: 359 us -> 387 us
Fixes https://obsproject.com/mantis/view.php?id=624
Fixes https://obsproject.com/mantis/view.php?id=1512
RGB to YUV converison was previously baked into every scale shader, but
this work has been moved to the YUV packing shaders. The scale shaders
now write RGBA instead. In the case where base and output resolutions
are identical, the render texture is forwarded directly to the YUV pack
step, skipping an entire fullscreen pass.
Intel GPA, SetStablePowerState, Intel HD Graphics 530, NV12
1920x1080, Before:
RGBA -> UYVX: ~321 us
UYVX -> Y: ~480 us
UYVX -> UV: ~127 us
1920x1080, After:
[forward render texture]
RGBA -> Y: ~487 us
RGBA -> UV: ~131 us
1920x1080 -> 1280x720, Before:
RGBA -> UYVX: ~268 us
UYVX -> Y: ~209 us
UYVX -> UV: ~57 us
1920x1080 -> 1280x720, After:
RGBA -> RGBA (rescale): ~268 us
RGBA -> Y: ~210 us
RGBA -> UV: ~58 us
Add a separate shader for area upscaling to take advantage of bilinear
filtering. Iterating over texels is unnecessary in the upscale case
because a target pixel can only overlap 1 or 2 texels in X and Y
directions. When only overlapping one texel, adjust UVs to sample texel
center to avoid filtering.
Also add "base_dimension" uniform to avoid unnecessary division.
Intel HD Graphics 530, 644x478 -> 1323x1080: ~836 us -> ~232 us
Code submissions have continually suffered from formatting
inconsistencies that constantly have to be addressed. Using
clang-format simplifies this by making code formatting more consistent,
and allows automation of the code formatting so that maintainers can
focus more on the code itself instead of code formatting.
The cache coherency of rasterization for full-screen passes is better
using an oversized triangle that is clipped rather than two triangles.
Traversal order of rasterization is GPU-specific, but will almost
certainly be better using an undivided primitive.
A smaller benefit is that quads along the diagonal are not evaluated
multiple times, but that's minor in comparison.
Redo format shaders to bypass vertex buffer, and input layout. Add
global shader bool "obs_glsl_compile" to make API-specific decisions,
i.e. handle upside-down UVs. gl_ortho is not needed for format
conversion because the vertex shader does not use ViewProj anymore.
This can be applied to more situations, but start small first.
Testbed full screen passes, Intel HD Graphics 530:
RGBA -> UYVX: 467 -> 439 us, ~6% savings
UYVX -> uv: 295 -> 239 us, ~19% savings
Remove three instances of unnecessary double-buffering. They are not
needed to avoid stalls, and cause increased memory traffic when
measured on Intel HD 530, presumably because texture data will remain
in cache if sampled immediately after write.
(Note: GPU timings from Intel GPA are volatile.)
NV12, 3 Draws:
RGBA -> UYVX: 628 us -> 543 us
UYVX -> Y: 522 us -> 507 us
UYVX -> UV: 315 us -> 187 us
Total, Duration: 1594 us -> 1153 us
Total, GTI Read Throughput: 25.2 MB -> 15.9 MB
There are cases where alpha is multiplied unnecessarily. This change
attempts to use premultiplied alpha blending for composition.
To keep this change simple, The filter chain will continue to use
straight alpha. Otherwise, every source would need to modified to output
premultiplied, and every filter modified for premultiplied input.
"DrawAlphaDivide" shader techniques have been added to convert from
premultiplied alpha to straight alpha for final output. "DrawMatrix"
techniques ignore alpha, so they do not appear to need changing.
One remaining issue is that scale effects are set up here to use the
same shader logic for both scale filters (straight alpha - incorrectly),
and output composition (premultiplied alpha - correctly). A fix could be
made to add additional shaders for straight alpha, but the "real" fix
may be to eliminate the straight alpha path at some point.
For graphics, SrcBlendAlpha and DestBlendAlpha were both ONE, and could
combine together to form alpha values greater than one. This is not as
noticeable of a problem for UNORM targets because the channels are
clamped, but it will likely become a problem in more situations if FLOAT
targets are used.
This change switches DestBlendAlpha to INVSRCALPHA. The blending
behavior of stacked transparents is preserved without overflowing the
alpha channel.
obs-transitions: Use premultiplied alpha blend, and simplify shaders
because both inputs and outputs use premultiplied alpha now.
Fixes https://obsproject.com/mantis/view.php?id=1108
Add D3D/GL debug markers to make RenderDoc captures easier to tranverse.
Also add obs_source_get_name_no_null() to avoid boilerplate for safe
string formatting.
Closesobsproject/obs-studio#1799
Currently SrcBlendAlpha and DestBlendAlpha are both ONE, and can
combine together to form two. This is not a noticeable problem for
UNORM targets because the channels are clamped, but it will likely
become a problem if FLOAT targets are more widely used.
This change switches DestBlendAlpha to INVSRCALPHA, and starts
backgrounds as opaque black instead of transparent black. The blending
behavior of stacked transparents is preserved without overflowing the
alpha channel.
Fixes the remaining case where a frame from the previous
recording/stream could show up at the beginning of the next
recording/stream on the same running session when using the new version
of NVENC. Textures are being converted for both raw and texture-based
encoders, so this variable which determines whether a texture is ready
and has been converted should be cleared in both cases.
When all outputs stop, and then the output starts back up again at a
later point after that, the last frame data or two from the previous
output session would end up as the first frame or two of the proceeding
output. This was because certain rendering variables were not being
properly cleared when a new output starts back up.
Uses obs_source_get_ref on the sources enumerated in the tick_sources
function in obs-video.c to ensure a reference has been incremented
before calling that source's video_tick, and replaces an
obs_source_addref with obs_source_get_ref in the push_audio_tree
function in obs-audio.c to ensure that it cannot increment a source that
has already decremented its reference to 0.
Allows the ability to encode by passing NV12 textures. This uses a
separate thread for texture-based encoders with a small queue of
textures. An output texture with a keyed mutex shared texture is locked
between OBS and each encoder. A new encoder callback and capability
flag is used to encode with textures.
Reduces GPU usage when encoding is not active. Does not perform color
conversion, frame staging, or frame downloading unless encoding is
explicitly active.
(Note: This commit also modifies UI and test)
This makes it so that main preview panes are rendered with the main
output texture rather than re-rendering the main view. The view will
render all objects again, whereas the output texture will be a single
texture render of the same exact thing.
Also fixes some abnormal artifacting when scaling the main preview pane.
This is to prevent confusion with video_thread in
libobs/media-io/video-io.c, which is used exclusively for video
encoding/output. Also prevents confusion in the profiler log data.
Allows getting the current active framerate that the core is rendering
with. This takes in to account any rendering lag or stalls that may be
occurring.
Allows the ability to use scale filters such as point, bicubic, lanczos
on specific scene items, disabled by default. When using one of the
latter two options, if the item's scale is under half of the source's
original size, it uses the bilinear low resolution downscale shader
instead.
This was originally used for calculating audio volume if transitions
were active, but transitions won't work that way so tracking the active
transitions is no longer needed.
Use explicit UTF-8 byte sequence for the "no-break space" character.
Prevents issues with certain editors, and fixes the following compiler
warning on Visual C++:
warning C4819: The file contains a character that cannot be represented
in the current code page (X). Save the file in Unicode format to prevent
data loss
(Non-compiling commit: windowless-context branch)
API Changed:
---------------------
Removed functions:
- obs_add_draw_callback
- obs_remove_draw_callback
- obs_resize
- obs_preview_set_enabled
- obs_preview_enabled
Removed member variables from struct obs_video_info:
- window_width
- window_height
- window
Summary:
---------------------
Changes the core libobs API to not be dependent upon a main window/view.
If you wish to draw to a window/view, use an obs_display object to
handle it.
This allows the use of libobs without requiring a window to be present
on the system. This is also prunes code that had to be needlessly
duplicated to handle the "main" window.
A minor optimization: in copy_rgbx_frame (used when libobs is set to
output RGBA frames instead of YUV frames), if the line sizes for the
source and destination match, just use a single memcpy call for all of
the data instead of multiple memcpy calls.
The "clamped" video time is the system time per video frame that is
closest to the current system time, but always divisible by the frame
interval. For example, if the last frame system timestamp was 1600 and
the new frame is 2500, but the frame interval is 800, then the
"clamped" video time is 2400.
This clamped value is useful to get the relative system time without any
jitter.
The normal scaling methods cannot sample enough pixels to create an
accurate output image when the output size is under half the base size,
so use the bilinear low resolution scaling effect in that case instead
to ensure a more accurate low resolution image.
jpark37
jp9000
James Park
Shaolin
Colin Edwards
Palana
Anthony Catel