IntSize CCVideoLayerImpl::computeVisibleSize(const WebKit::WebVideoFrame& frame, unsigned plane)
{
int visibleWidth = videoFrameDimension(frame.width(), plane, frame.format());
int originalWidth = visibleWidth;
int visibleHeight = videoFrameDimension(frame.height(), plane, frame.format());
// When there are dead pixels at the edge of the texture, decrease
// the frame width by 1 to prevent the rightmost pixels from
// interpolating with the dead pixels.
if (hasPaddingBytes(frame, plane))
--visibleWidth;
// In YV12, every 2x2 square of Y values corresponds to one U and
// one V value. If we decrease the width of the UV plane, we must decrease the
// width of the Y texture by 2 for proper alignment. This must happen
// always, even if Y's texture does not have padding bytes.
if (plane == WebKit::WebVideoFrame::yPlane && frame.format() == WebKit::WebVideoFrame::FormatYV12) {
if (hasPaddingBytes(frame, WebKit::WebVideoFrame::uPlane))
visibleWidth = originalWidth - 2;
}
return IntSize(visibleWidth, visibleHeight);
}
// Convert WebKit::WebVideoFrame::Format to GraphicsContext3D's format enum values.
static GC3Denum convertVFCFormatToGC3DFormat(const WebKit::WebVideoFrame& frame)
{
switch (frame.format()) {
case WebKit::WebVideoFrame::FormatYV12:
case WebKit::WebVideoFrame::FormatYV16:
return GraphicsContext3D::LUMINANCE;
case WebKit::WebVideoFrame::FormatNativeTexture:
return frame.textureTarget();
case WebKit::WebVideoFrame::FormatInvalid:
case WebKit::WebVideoFrame::FormatRGB32:
case WebKit::WebVideoFrame::FormatEmpty:
case WebKit::WebVideoFrame::FormatI420:
notImplemented();
}
return GraphicsContext3D::INVALID_VALUE;
}
static bool hasPaddingBytes(const WebKit::WebVideoFrame& frame, unsigned plane)
{
return frame.stride(plane) > videoFrameDimension(frame.width(), plane, frame.format());
}
bool CCVideoLayerImpl::reserveTextures(const WebKit::WebVideoFrame& frame, GC3Denum format, LayerRendererChromium* layerRenderer)
{
if (frame.planes() > MaxPlanes)
return false;
int maxTextureSize = layerRenderer->capabilities().maxTextureSize;
for (unsigned plane = 0; plane < frame.planes(); ++plane) {
IntSize requiredTextureSize(frame.stride(plane), videoFrameDimension(frame.height(), plane, frame.format()));
// If the renderer cannot handle this large of a texture, return false.
// FIXME: Remove this test when tiled layers are implemented.
if (requiredTextureSize.isZero() || requiredTextureSize.width() > maxTextureSize || requiredTextureSize.height() > maxTextureSize)
return false;
if (!m_textures[plane].m_texture) {
m_textures[plane].m_texture = ManagedTexture::create(layerRenderer->renderSurfaceTextureManager());
if (!m_textures[plane].m_texture)
return false;
m_textures[plane].m_visibleSize = IntSize();
} else {
// The renderSurfaceTextureManager may have been destroyed and recreated since the last frame, so pass the new one.
// This is a no-op if the TextureManager is still around.
m_textures[plane].m_texture->setTextureManager(layerRenderer->renderSurfaceTextureManager());
}
if (m_textures[plane].m_texture->size() != requiredTextureSize)
m_textures[plane].m_visibleSize = computeVisibleSize(frame, plane);
if (!m_textures[plane].m_texture->reserve(requiredTextureSize, format))
return false;
}
return true;
}