Working

SHADER_CONTRACT.md

@@ -26,7 +26,7 @@ Supported parameter types:
 
 ## Slang contract
 
-The runtime owns the fragment entry point, video decode, and final mix/bypass behavior.
+The runtime owns the fragment entry point, the UYVY-to-RGBA decode pass, and final mix/bypass behavior.
 
 Your `shader.slang` file implements:
 
@@ -40,7 +40,7 @@ float4 shadeVideo(ShaderContext context)
 Available built-ins through `ShaderContext`:
 
 - `uv`
-- `sourceColor`
+- `sourceColor` - the already-decoded full-resolution RGBA video color at `uv`
 - `inputResolution`
 - `outputResolution`
 - `time`
@@ -52,4 +52,4 @@ Manifest parameters are exposed to the shader as globals named by their `id`.
 
 Helper function:
 
-- `sampleVideo(float2 uv)` returns decoded RGBA video from the live DeckLink input.
+- `sampleVideo(float2 uv)` returns decoded full-resolution RGBA video from the live DeckLink input.