From 032df7f18ff4e8b517ca32d5a107a9b7d972192a Mon Sep 17 00:00:00 2001
From: Vojtech Bubnik <bubnikv@gmail.com>
Date: Mon, 22 Feb 2021 18:07:15 +0100
Subject: [PATCH] PNGReadWrite: png::write_gray_to_file(),
png::write_gray_to_file_scaled()
---
src/libslic3r/PNGReadWrite.cpp | 77 +++++++++++++++++++++++++++-------
src/libslic3r/PNGReadWrite.hpp | 10 +++++
2 files changed, 72 insertions(+), 15 deletions(-)
diff --git a/src/libslic3r/PNGReadWrite.cpp b/src/libslic3r/PNGReadWrite.cpp
index 1e8a7de53..f04ccd6ef 100644
--- a/src/libslic3r/PNGReadWrite.cpp
+++ b/src/libslic3r/PNGReadWrite.cpp
@@ -102,7 +102,8 @@ bool decode_png(IStream &in_buf, ImageGreyscale &out_img)
// Down to earth function to store a packed RGB image to file. Mostly useful for debugging purposes.
// Based on https://www.lemoda.net/c/write-png/
-bool write_rgb_to_file(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb)
+// png_color_type is PNG_COLOR_TYPE_RGB or PNG_COLOR_TYPE_GRAY
+static bool write_rgb_or_gray_to_file(const char *file_name_utf8, size_t width, size_t height, int png_color_type, const uint8_t *data)
{
bool result = false;
@@ -141,17 +142,20 @@ bool write_rgb_to_file(const char *file_name_utf8, size_t width, size_t height,
png_uint_32(width),
png_uint_32(height),
8, // depth
- PNG_COLOR_TYPE_RGB,
+ png_color_type,
PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT);
// Initialize rows of PNG.
row_pointers = reinterpret_cast<png_byte**>(::png_malloc(png_ptr, height * sizeof(png_byte*)));
+ int line_width = width;
+ if (png_color_type == PNG_COLOR_TYPE_RGB)
+ line_width *= 3;
for (size_t y = 0; y < height; ++ y) {
- auto row = reinterpret_cast<png_byte*>(::png_malloc(png_ptr, sizeof(uint8_t) * width * 3));
+ auto row = reinterpret_cast<png_byte*>(::png_malloc(png_ptr, line_width));
row_pointers[y] = row;
- memcpy(row, data_rgb + width * y * 3, sizeof(uint8_t) * width * 3);
+ memcpy(row, data + line_width * y, line_width);
}
// Write the image data to "fp".
@@ -174,6 +178,11 @@ fopen_failed:
return result;
}
+bool write_rgb_to_file(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb)
+{
+ return write_rgb_or_gray_to_file(file_name_utf8, width, height, PNG_COLOR_TYPE_RGB, data_rgb);
+}
+
bool write_rgb_to_file(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb)
{
return write_rgb_to_file(file_name_utf8.c_str(), width, height, data_rgb);
@@ -185,32 +194,54 @@ bool write_rgb_to_file(const std::string &file_name_utf8, size_t width, size_t h
return write_rgb_to_file(file_name_utf8.c_str(), width, height, data_rgb.data());
}
+bool write_gray_to_file(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_gray)
+{
+ return write_rgb_or_gray_to_file(file_name_utf8, width, height, PNG_COLOR_TYPE_GRAY, data_gray);
+}
+
+bool write_gray_to_file(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_gray)
+{
+ return write_gray_to_file(file_name_utf8.c_str(), width, height, data_gray);
+}
+
+bool write_gray_to_file(const std::string &file_name_utf8, size_t width, size_t height, const std::vector<uint8_t> &data_gray)
+{
+ assert(width * height == data_gray.size());
+ return write_gray_to_file(file_name_utf8.c_str(), width, height, data_gray.data());
+}
+
// Scaled variants are mostly useful for debugging purposes, for example to export images of low resolution distance fileds.
// Scaling is done by multiplying rows and columns without any smoothing to emphasise the original pixels.
-bool write_rgb_to_file_scaled(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb, size_t scale)
+// png_color_type is PNG_COLOR_TYPE_RGB or PNG_COLOR_TYPE_GRAY
+static bool write_rgb_or_gray_to_file_scaled(const char *file_name_utf8, size_t width, size_t height, int png_color_type, const uint8_t *data, size_t scale)
{
if (scale <= 1)
- return write_rgb_to_file(file_name_utf8, width, height, data_rgb);
+ return write_rgb_or_gray_to_file(file_name_utf8, width, height, png_color_type, data);
else {
- std::vector<uint8_t> scaled(width * height * 3 * scale * scale);
+ size_t pixel_bytes = png_color_type == PNG_COLOR_TYPE_RGB ? 3 : 1;
+ size_t line_width = width * pixel_bytes;
+ std::vector<uint8_t> scaled(line_width * height * scale * scale);
uint8_t *dst = scaled.data();
for (size_t r = 0; r < height; ++ r) {
for (size_t repr = 0; repr < scale; ++ repr) {
- const uint8_t *row = data_rgb + width * 3 * r;
+ const uint8_t *row = data + line_width * r;
for (size_t c = 0; c < width; ++ c) {
- for (size_t repc = 0; repc < scale; ++ repc) {
- *dst ++ = row[0];
- *dst ++ = row[1];
- *dst ++ = row[2];
- }
- row += 3;
+ for (size_t repc = 0; repc < scale; ++ repc)
+ for (size_t b = 0; b < pixel_bytes; ++ b)
+ *dst ++ = row[b];
+ row += pixel_bytes;
}
}
}
- return write_rgb_to_file(file_name_utf8, width * scale, height * scale, scaled.data());
+ return write_rgb_or_gray_to_file(file_name_utf8, width * scale, height * scale, png_color_type, scaled.data());
}
}
+bool write_rgb_to_file_scaled(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb, size_t scale)
+{
+ return write_rgb_or_gray_to_file_scaled(file_name_utf8, width, height, PNG_COLOR_TYPE_RGB, data_rgb, scale);
+}
+
bool write_rgb_to_file_scaled(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb, size_t scale)
{
return write_rgb_to_file_scaled(file_name_utf8.c_str(), width, height, data_rgb, scale);
@@ -222,4 +253,20 @@ bool write_rgb_to_file_scaled(const std::string &file_name_utf8, size_t width, s
return write_rgb_to_file_scaled(file_name_utf8.c_str(), width, height, data_rgb.data(), scale);
}
+bool write_gray_to_file_scaled(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_gray, size_t scale)
+{
+ return write_rgb_or_gray_to_file_scaled(file_name_utf8, width, height, PNG_COLOR_TYPE_GRAY, data_gray, scale);
+}
+
+bool write_gray_to_file_scaled(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_gray, size_t scale)
+{
+ return write_gray_to_file_scaled(file_name_utf8.c_str(), width, height, data_gray, scale);
+}
+
+bool write_gray_to_file_scaled(const std::string &file_name_utf8, size_t width, size_t height, const std::vector<uint8_t> &data_gray, size_t scale)
+{
+ assert(width * height == data_gray.size());
+ return write_gray_to_file_scaled(file_name_utf8.c_str(), width, height, data_gray.data(), scale);
+}
+
}} // namespace Slic3r::png
diff --git a/src/libslic3r/PNGReadWrite.hpp b/src/libslic3r/PNGReadWrite.hpp
index 6be8ed555..01e1f4745 100644
--- a/src/libslic3r/PNGReadWrite.hpp
+++ b/src/libslic3r/PNGReadWrite.hpp
@@ -71,11 +71,21 @@ template<class Img> bool decode_png(const ReadBuf &in_buf, Img &out_img)
bool write_rgb_to_file(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb);
bool write_rgb_to_file(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb);
bool write_rgb_to_file(const std::string &file_name_utf8, size_t width, size_t height, const std::vector<uint8_t> &data_rgb);
+// Grayscale variants
+bool write_gray_to_file(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_gray);
+bool write_gray_to_file(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_gray);
+bool write_gray_to_file(const std::string &file_name_utf8, size_t width, size_t height, const std::vector<uint8_t> &data_gray);
+
// Scaled variants are mostly useful for debugging purposes, for example to export images of low resolution distance fileds.
// Scaling is done by multiplying rows and columns without any smoothing to emphasise the original pixels.
bool write_rgb_to_file_scaled(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb, size_t scale);
bool write_rgb_to_file_scaled(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_rgb, size_t scale);
bool write_rgb_to_file_scaled(const std::string &file_name_utf8, size_t width, size_t height, const std::vector<uint8_t> &data_rgb, size_t scale);
+// Grayscale variants
+bool write_gray_to_file_scaled(const char *file_name_utf8, size_t width, size_t height, const uint8_t *data_gray, size_t scale);
+bool write_gray_to_file_scaled(const std::string &file_name_utf8, size_t width, size_t height, const uint8_t *data_gray, size_t scale);
+bool write_gray_to_file_scaled(const std::string &file_name_utf8, size_t width, size_t height, const std::vector<uint8_t> &data_gray, size_t scale);
+
}} // namespace Slic3r::png