ResizeConversion::ResizeConversion(unsigned src_width, unsigned src_height, PixelType type) :
src_width{ src_width },
src_height{ src_height },
type{ type },
depth{ pixel_depth(type) },
filter{},
dst_width{ src_width },
dst_height{ src_height },
shift_w{},
shift_h{},
subwidth{ (double)src_width },
subheight{ (double)src_height },
cpu{ CPUClass::CPU_NONE }
{
}
void validate_state(const GraphBuilder::state &state)
{
if (!state.width || !state.height)
throw error::ZeroImageSize{ "image dimensions must be non-zero" };
if (is_greyscale(state)) {
if (state.subsample_w || state.subsample_h)
throw error::GreyscaleSubsampling{ "cannot subsample greyscale image" };
if (state.colorspace.matrix == zimg::colorspace::MatrixCoefficients::MATRIX_RGB)
throw error::ColorFamilyMismatch{ "GREY color family cannot be RGB" };
}
if (is_rgb(state)) {
if (state.subsample_w || state.subsample_h)
throw zimg::error::UnsupportedSubsampling{ "subsampled RGB image not supported" };
if (state.colorspace.matrix != zimg::colorspace::MatrixCoefficients::MATRIX_UNSPECIFIED &&
state.colorspace.matrix != zimg::colorspace::MatrixCoefficients::MATRIX_RGB)
throw error::ColorFamilyMismatch{ "RGB color family cannot be YUV" };
}
if (is_yuv(state)) {
if (state.colorspace.matrix == zimg::colorspace::MatrixCoefficients::MATRIX_RGB)
throw error::ColorFamilyMismatch{ "YUV color family cannot be RGB" };
}
if (state.subsample_h > 1 && state.parity != GraphBuilder::FieldParity::FIELD_PROGRESSIVE)
throw error::UnsupportedSubsampling{ "vertical subsampling greater than 2x is not supported" };
if (state.subsample_w > 2 || state.subsample_h > 2)
throw error::UnsupportedSubsampling{ "subsampling greater than 4x is not supported" };
if (state.width % (1 << state.subsample_w) || state.height % (1 << state.subsample_h))
throw error::ImageNotDivislbe{ "image dimensions must be divisible by subsampling factor" };
if (state.depth > pixel_depth(state.type))
throw error::BitDepthOverflow{ "bit depth exceeds limits of type" };
if (!state.fullrange && state.depth < 8)
throw error::BitDepthOverflow{ "bit depth must be at least 8 for limited range" };
}
