Files
test2/source/blender/compositor/operations/COM_ImageOperation.cc
Aras Pranckevicius 0bfffdaf82 VSE: bilinear upscaling no longer adds transparent border around the image
Part of overall "improve image filtering situation" (#116980), this PR addresses
two issues:
- Bilinear (default) image filtering makes half a source pixel wide transparent
  border around the image. This is very noticeable when scaling images/movies up
  in VSE. However, when there is no scaling up but you have slightly rotated
  image, this creates a "somewhat nice" anti-aliasing around the edge.
- The other filtering kinds (e.g. cubic) do not have this behavior. So they do
  not create unexpected transparency when scaling up (yay), however for slightly
  rotated images the edge is "jagged" (oh no).

More detail and images in PR.

Pull Request: https://projects.blender.org/blender/blender/pulls/117717
2024-02-02 16:28:51 +01:00

188 lines
5.3 KiB
C++

/* SPDX-FileCopyrightText: 2011 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
#include "COM_ImageOperation.h"
#include "BKE_scene.h"
#include "IMB_colormanagement.hh"
#include "IMB_interp.hh"
namespace blender::compositor {
BaseImageOperation::BaseImageOperation()
{
image_ = nullptr;
buffer_ = nullptr;
image_float_buffer_ = nullptr;
image_byte_buffer_ = nullptr;
image_user_ = nullptr;
imagewidth_ = 0;
imageheight_ = 0;
framenumber_ = 0;
number_of_channels_ = 0;
rd_ = nullptr;
view_name_ = nullptr;
}
ImageOperation::ImageOperation() : BaseImageOperation()
{
this->add_output_socket(DataType::Color);
}
ImageAlphaOperation::ImageAlphaOperation() : BaseImageOperation()
{
this->add_output_socket(DataType::Value);
}
ImBuf *BaseImageOperation::get_im_buf()
{
ImBuf *ibuf;
ImageUser iuser = *image_user_;
if (image_ == nullptr) {
return nullptr;
}
/* local changes to the original ImageUser */
if (BKE_image_is_multilayer(image_) == false) {
iuser.multi_index = BKE_scene_multiview_view_id_get(rd_, view_name_);
}
ibuf = BKE_image_acquire_ibuf(image_, &iuser, nullptr);
if (ibuf == nullptr || (ibuf->byte_buffer.data == nullptr && ibuf->float_buffer.data == nullptr))
{
BKE_image_release_ibuf(image_, ibuf, nullptr);
return nullptr;
}
return ibuf;
}
void BaseImageOperation::init_execution()
{
ImBuf *stackbuf = get_im_buf();
buffer_ = stackbuf;
if (stackbuf) {
image_float_buffer_ = stackbuf->float_buffer.data;
image_byte_buffer_ = stackbuf->byte_buffer.data;
imagewidth_ = stackbuf->x;
imageheight_ = stackbuf->y;
number_of_channels_ = stackbuf->channels;
}
}
void BaseImageOperation::deinit_execution()
{
image_float_buffer_ = nullptr;
image_byte_buffer_ = nullptr;
BKE_image_release_ibuf(image_, buffer_, nullptr);
}
void BaseImageOperation::determine_canvas(const rcti & /*preferred_area*/, rcti &r_area)
{
ImBuf *stackbuf = get_im_buf();
r_area = COM_AREA_NONE;
if (stackbuf) {
BLI_rcti_init(&r_area, 0, stackbuf->x, 0, stackbuf->y);
}
BKE_image_release_ibuf(image_, stackbuf, nullptr);
}
static void sample_image_at_location(ImBuf *ibuf,
float x,
float y,
PixelSampler sampler,
bool make_linear_rgb,
bool ensure_premultiplied,
float color[4])
{
if (ibuf->float_buffer.data) {
switch (sampler) {
case PixelSampler::Nearest:
imbuf::interpolate_nearest_fl(ibuf, color, x, y);
break;
case PixelSampler::Bilinear:
imbuf::interpolate_bilinear_border_fl(ibuf, color, x, y);
break;
case PixelSampler::Bicubic:
imbuf::interpolate_cubic_bspline_fl(ibuf, color, x, y);
break;
}
}
else {
uchar4 byte_color;
switch (sampler) {
case PixelSampler::Nearest:
byte_color = imbuf::interpolate_nearest_byte(ibuf, x, y);
break;
case PixelSampler::Bilinear:
byte_color = imbuf::interpolate_bilinear_border_byte(ibuf, x, y);
break;
case PixelSampler::Bicubic:
byte_color = imbuf::interpolate_cubic_bspline_byte(ibuf, x, y);
break;
}
rgba_uchar_to_float(color, byte_color);
if (make_linear_rgb) {
IMB_colormanagement_colorspace_to_scene_linear_v4(
color, false, ibuf->byte_buffer.colorspace);
}
if (ensure_premultiplied) {
straight_to_premul_v4(color);
}
}
}
void ImageOperation::execute_pixel_sampled(float output[4], float x, float y, PixelSampler sampler)
{
int ix = x, iy = y;
if (image_float_buffer_ == nullptr && image_byte_buffer_ == nullptr) {
zero_v4(output);
}
else if (ix < 0 || iy < 0 || ix >= buffer_->x || iy >= buffer_->y) {
zero_v4(output);
}
else {
const bool ensure_premultiplied = !ELEM(
image_->alpha_mode, IMA_ALPHA_CHANNEL_PACKED, IMA_ALPHA_IGNORE);
sample_image_at_location(buffer_, x, y, sampler, true, ensure_premultiplied, output);
}
}
void ImageOperation::update_memory_buffer_partial(MemoryBuffer *output,
const rcti &area,
Span<MemoryBuffer *> /*inputs*/)
{
const bool ensure_premultiplied = !ELEM(
image_->alpha_mode, IMA_ALPHA_CHANNEL_PACKED, IMA_ALPHA_IGNORE);
output->copy_from(buffer_, area, ensure_premultiplied, true);
}
void ImageAlphaOperation::execute_pixel_sampled(float output[4],
float x,
float y,
PixelSampler sampler)
{
float tempcolor[4];
if (image_float_buffer_ == nullptr && image_byte_buffer_ == nullptr) {
output[0] = 0.0f;
}
else {
tempcolor[3] = 1.0f;
sample_image_at_location(buffer_, x, y, sampler, false, false, tempcolor);
output[0] = tempcolor[3];
}
}
void ImageAlphaOperation::update_memory_buffer_partial(MemoryBuffer *output,
const rcti &area,
Span<MemoryBuffer *> /*inputs*/)
{
output->copy_from(buffer_, area, 3, COM_DATA_TYPE_VALUE_CHANNELS, 0);
}
} // namespace blender::compositor