@@ -9,8 +9,10 @@ attribute vec4 vertexIn;
attribute vec2 textureIn;
varying vec2 textureOut;
+uniform float stride_factor;
+
void main(void)
{
gl_Position = vertexIn;
- textureOut = textureIn;
+ textureOut = vec2(textureIn.x * stride_factor, textureIn.y);
}
@@ -395,6 +395,7 @@ bool ViewFinderGL::createFragmentShader()
textureUniformV_ = shaderProgram_.uniformLocation("tex_v");
textureUniformStep_ = shaderProgram_.uniformLocation("tex_step");
textureUniformSize_ = shaderProgram_.uniformLocation("tex_size");
+ textureUniformStrideFactor_ = shaderProgram_.uniformLocation("stride_factor");
textureUniformBayerFirstRed_ = shaderProgram_.uniformLocation("tex_bayer_first_red");
/* Create the textures. */
@@ -464,6 +465,9 @@ void ViewFinderGL::initializeGL()
void ViewFinderGL::doRender()
{
+ /* Stride of the first plane, in pixels. */
+ unsigned int stridePixels;
+
switch (format_) {
case libcamera::formats::NV12:
case libcamera::formats::NV21:
@@ -477,7 +481,7 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE,
- size_.width(),
+ stride_,
size_.height(),
0,
GL_LUMINANCE,
@@ -491,13 +495,15 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE_ALPHA,
- size_.width() / horzSubSample_,
+ stride_ / horzSubSample_,
size_.height() / vertSubSample_,
0,
GL_LUMINANCE_ALPHA,
GL_UNSIGNED_BYTE,
image_->data(1).data());
shaderProgram_.setUniformValue(textureUniformU_, 1);
+
+ stridePixels = stride_;
break;
case libcamera::formats::YUV420:
@@ -507,7 +513,7 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE,
- size_.width(),
+ stride_,
size_.height(),
0,
GL_LUMINANCE,
@@ -521,7 +527,7 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE,
- size_.width() / horzSubSample_,
+ stride_ / horzSubSample_,
size_.height() / vertSubSample_,
0,
GL_LUMINANCE,
@@ -535,13 +541,15 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE,
- size_.width() / horzSubSample_,
+ stride_ / horzSubSample_,
size_.height() / vertSubSample_,
0,
GL_LUMINANCE,
GL_UNSIGNED_BYTE,
image_->data(2).data());
shaderProgram_.setUniformValue(textureUniformV_, 2);
+
+ stridePixels = stride_;
break;
case libcamera::formats::YVU420:
@@ -551,7 +559,7 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE,
- size_.width(),
+ stride_,
size_.height(),
0,
GL_LUMINANCE,
@@ -565,7 +573,7 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE,
- size_.width() / horzSubSample_,
+ stride_ / horzSubSample_,
size_.height() / vertSubSample_,
0,
GL_LUMINANCE,
@@ -579,13 +587,15 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_LUMINANCE,
- size_.width() / horzSubSample_,
+ stride_ / horzSubSample_,
size_.height() / vertSubSample_,
0,
GL_LUMINANCE,
GL_UNSIGNED_BYTE,
image_->data(2).data());
shaderProgram_.setUniformValue(textureUniformU_, 1);
+
+ stridePixels = stride_;
break;
case libcamera::formats::UYVY:
@@ -602,7 +612,7 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_RGBA,
- size_.width() / 2,
+ stride_ / 4,
size_.height(),
0,
GL_RGBA,
@@ -619,6 +629,8 @@ void ViewFinderGL::doRender()
shaderProgram_.setUniformValue(textureUniformStep_,
1.0f / (size_.width() / 2 - 1),
1.0f /* not used */);
+
+ stridePixels = stride_ / 2;
break;
case libcamera::formats::ABGR8888:
@@ -630,13 +642,15 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_RGBA,
- size_.width(),
+ stride_ / 4,
size_.height(),
0,
GL_RGBA,
GL_UNSIGNED_BYTE,
image_->data(0).data());
shaderProgram_.setUniformValue(textureUniformY_, 0);
+
+ stridePixels = stride_ / 4;
break;
case libcamera::formats::BGR888:
@@ -646,13 +660,15 @@ void ViewFinderGL::doRender()
glTexImage2D(GL_TEXTURE_2D,
0,
GL_RGB,
- size_.width(),
+ stride_ / 3,
size_.height(),
0,
GL_RGB,
GL_UNSIGNED_BYTE,
image_->data(0).data());
shaderProgram_.setUniformValue(textureUniformY_, 0);
+
+ stridePixels = stride_ / 3;
break;
case libcamera::formats::SBGGR8:
@@ -692,11 +708,27 @@ void ViewFinderGL::doRender()
shaderProgram_.setUniformValue(textureUniformStep_,
1.0f / (stride_ - 1),
1.0f / (size_.height() - 1));
+
+ /*
+ * The stride is already taken into account in the shaders, set
+ * the generic stride factor to 1.0.
+ */
+ stridePixels = size_.width();
break;
default:
+ stridePixels = size_.width();
break;
};
+
+ /*
+ * Compute the stride factor for the vertex shader, to map the
+ * horizontal texture coordinate range [0.0, 1.0] to the active portion
+ * of the image.
+ */
+ shaderProgram_.setUniformValue(textureUniformStrideFactor_,
+ static_cast<float>(size_.width() - 1) /
+ (stridePixels - 1));
}
void ViewFinderGL::paintGL()
@@ -97,6 +97,7 @@ private:
/* Raw Bayer texture parameters */
GLuint textureUniformSize_;
+ GLuint textureUniformStrideFactor_;
GLuint textureUniformBayerFirstRed_;
QPointF firstRed_;
The RGB and YUV conversion doesn't take the stride into account, neither when creating the textures, nor when sampling them. Fix it by using the stride as the texture width, and multiplying the x coordinate in the vertex shaders by a factor to only sample the active portion of the image. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> --- src/qcam/assets/shader/identity.vert | 4 ++- src/qcam/viewfinder_gl.cpp | 54 ++++++++++++++++++++++------ src/qcam/viewfinder_gl.h | 1 + 3 files changed, 47 insertions(+), 12 deletions(-)