Image API: Refactor. Return original bit depth of the image.

Ghabry · Apr 15, 2024 · 0f6f8fb · 0f6f8fb
1 parent 9c29b62
commit 0f6f8fb
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Showing 8 changed files with 97 additions and 73 deletions.
diff --git a/src/bitmap.cpp b/src/bitmap.cpp
@@ -99,67 +99,66 @@ Bitmap::Bitmap(Filesystem_Stream::InputStream stream, bool transparent, uint32_t
 		return;
 	}
 
-	int w = 0;
-	int h = 0;
-	void* pixels = nullptr;
+	ImageOut image_out;
 
 	uint8_t data[4] = {};
 	size_t bytes = stream.read(reinterpret_cast<char*>(data),  4).gcount();
 	stream.seekg(0, std::ios::ios_base::beg);
 
 	bool img_okay = false;
 
-	if (bytes >= 4 && strncmp((char*)data, "XYZ1", 4) == 0)
-		img_okay = ImageXYZ::ReadXYZ(stream, transparent, w, h, pixels);
-	else if (bytes > 2 && strncmp((char*)data, "BM", 2) == 0)
-		img_okay = ImageBMP::ReadBMP(stream, transparent, w, h, pixels);
-	else if (bytes >= 4 && strncmp((char*)(data + 1), "PNG", 3) == 0)
-		img_okay = ImagePNG::ReadPNG(stream, transparent, w, h, pixels);
-	else
+	if (bytes >= 4 && strncmp((char*)data, "XYZ1", 4) == 0) {
+		img_okay = ImageXYZ::Read(stream, transparent, image_out);
+	} else if (bytes > 2 && strncmp((char*)data, "BM", 2) == 0) {
+		img_okay = ImageBMP::Read(stream, transparent, image_out);
+	} else if (bytes >= 4 && strncmp((char*)(data + 1), "PNG", 3) == 0) {
+		img_okay = ImagePNG::Read(stream, transparent, image_out);
+	} else
 		Output::Warning("Unsupported image file {} (Magic: {:02X})", stream.GetName(), *reinterpret_cast<uint32_t*>(data));
 
 	if (!img_okay) {
-		free(pixels);
-		pixels = nullptr;
+		free(image_out.pixels);
 		return;
 	}
 
-	Init(w, h, nullptr);
+	Init(image_out.width, image_out.height, nullptr);
 
-	ConvertImage(w, h, pixels, transparent);
+	ConvertImage(image_out.width, image_out.height, image_out.pixels, transparent);
 
 	CheckPixels(flags);
 
+	original_bpp = image_out.bpp;
+
 	filename = ToString(stream.GetName());
 }
 
 Bitmap::Bitmap(const uint8_t* data, unsigned bytes, bool transparent, uint32_t flags) {
 	format = (transparent ? pixel_format : opaque_pixel_format);
 	pixman_format = find_format(format);
 
-	int w = 0, h = 0;
-	void* pixels = nullptr;
+	ImageOut image_out;
 
 	bool img_okay = false;
 
 	if (bytes > 4 && strncmp((char*) data, "XYZ1", 4) == 0)
-		img_okay = ImageXYZ::ReadXYZ(data, bytes, transparent, w, h, pixels);
+		img_okay = ImageXYZ::Read(data, bytes, transparent, image_out);
 	else if (bytes > 2 && strncmp((char*) data, "BM", 2) == 0)
-		img_okay = ImageBMP::ReadBMP(data, bytes, transparent, w, h, pixels);
+		img_okay = ImageBMP::Read(data, bytes, transparent, image_out);
 	else if (bytes > 4 && strncmp((char*)(data + 1), "PNG", 3) == 0)
-		img_okay = ImagePNG::ReadPNG((const void*) data, transparent, w, h, pixels);
+		img_okay = ImagePNG::Read((const void*) data, transparent, image_out);
 	else
 		Output::Warning("Unsupported image (Magic: {:02X})", bytes >= 4 ? *reinterpret_cast<const uint32_t*>(data) : 0);
 
 	if (!img_okay) {
-		free(pixels);
-		pixels = nullptr;
+		free(image_out.pixels);
 		return;
 	}
 
-	Init(w, h, nullptr);
+	Init(image_out.width, image_out.height, nullptr);
+
+	ConvertImage(image_out.width, image_out.height, image_out.pixels, transparent);
 
-	ConvertImage(w, h, pixels, transparent);
+	original_bpp = image_out.bpp;
 
 	CheckPixels(flags);
 }
@@ -183,7 +182,7 @@ bool Bitmap::WritePNG(std::ostream& os) const {
 	pixman_image_composite32(PIXMAN_OP_SRC, bitmap.get(), NULL, dst.get(),
 							 0, 0, 0, 0, 0, 0, width, height);
 
-	return ImagePNG::WritePNG(os, width, height, &data.front());
+	return ImagePNG::Write(os, width, height, &data.front());
 }
 
 size_t Bitmap::GetSize() const {

diff --git a/src/bitmap.h b/src/bitmap.h
@@ -224,6 +224,13 @@ class Bitmap {
 	 */
 	StringView GetFilename() const;
 
+	/**
+	 * Gets bpp of the source image.
+	 *
+	 * @return Bpp
+	 */
+	int GetOriginalBpp() const;
+
 	void CheckPixels(uint32_t flags);
 
 	/**
@@ -599,6 +606,9 @@ class Bitmap {
 
 	std::string filename;
 
+	/** Bpp of the source image */
+	int original_bpp;
+
 	/** Bitmap data. */
 	PixmanImagePtr bitmap;
 	pixman_format_code_t pixman_format;
@@ -636,6 +646,13 @@ class Bitmap {
 	bool read_only = false;
 };
 
+struct ImageOut {
+	int width = 0;
+	int height = 0;
+	void* pixels = nullptr;
+	int bpp = 0;
+};
+
 inline ImageOpacity Bitmap::GetImageOpacity() const {
 	return image_opacity;
 }
@@ -672,4 +689,8 @@ inline StringView Bitmap::GetFilename() const {
 	return filename;
 }
 
+inline int Bitmap::GetOriginalBpp() const {
+	return original_bpp;
+}
+
 #endif
diff --git a/src/image_bmp.cpp b/src/image_bmp.cpp
@@ -84,9 +84,8 @@ ImageBMP::BitmapHeader ImageBMP::ParseHeader(const uint8_t*& ptr, uint8_t const*
 	return hdr;
 }
 
-bool ImageBMP::ReadBMP(const uint8_t* data, unsigned len, bool transparent,
-					   int& width, int& height, void*& pixels) {
-	pixels = nullptr;
+bool ImageBMP::Read(const uint8_t* data, unsigned len, bool transparent, ImageOut& output) {
+	output.pixels = nullptr;
 
 	if (len < 64) {
 		Output::Warning("Not a valid BMP file.");
@@ -142,13 +141,13 @@ bool ImageBMP::ReadBMP(const uint8_t* data, unsigned len, bool transparent,
 	int line_width = (hdr.depth == 4) ? (hdr.w + 1) >> 1 : hdr.w;
 	int padding = (-line_width)&3;
 
-	pixels = malloc(hdr.w * hdr.h * 4);
-	if (!pixels) {
+	output.pixels = malloc(hdr.w * hdr.h * 4);
+	if (!output.pixels) {
 		Output::Warning("Error allocating BMP pixel buffer.");
 		return false;
 	}
 
-	uint8_t* dst = (uint8_t*) pixels;
+	uint8_t* dst = (uint8_t*) output.pixels;
 	for (int y = 0; y < hdr.h; y++) {
 		const uint8_t* src = src_pixels + (vflip ? hdr.h - 1 - y : y) * (line_width + padding);
 		for (int x = 0; x < hdr.w; x += 2) {
@@ -182,13 +181,13 @@ bool ImageBMP::ReadBMP(const uint8_t* data, unsigned len, bool transparent,
 		}
 	}
 
-	width = hdr.w;
-	height = hdr.h;
+	output.width = hdr.w;
+	output.height = hdr.h;
+	output.bpp = hdr.depth; // Currently only 4 and 8 bit (indexed) are supported
 	return true;
 }
 
-bool ImageBMP::ReadBMP(Filesystem_Stream::InputStream& stream, bool transparent,
-					int& width, int& height, void*& pixels) {
+bool ImageBMP::Read(Filesystem_Stream::InputStream& stream, bool transparent, ImageOut& output) {
 	std::vector<uint8_t> buffer = Utils::ReadStream(stream);
-	return ReadBMP(&buffer.front(), (unsigned) buffer.size(), transparent, width, height, pixels);
+	return Read(&buffer.front(), (unsigned) buffer.size(), transparent, output);
 }
diff --git a/src/image_bmp.h b/src/image_bmp.h
@@ -19,6 +19,7 @@
 #define EP_IMAGE_BMP_H
 
 #include <cstdint>
+#include "bitmap.h"
 #include "filesystem_stream.h"
 
 namespace ImageBMP {
@@ -33,8 +34,8 @@ namespace ImageBMP {
 		int palette_size = 0;
 	};
 
-	bool ReadBMP(const uint8_t* data, unsigned len, bool transparent, int& width, int& height, void*& pixels);
-	bool ReadBMP(Filesystem_Stream::InputStream& stream, bool transparent, int& width, int& height, void*& pixels);
+	bool Read(const uint8_t* data, unsigned len, bool transparent, ImageOut& output);
+	bool Read(Filesystem_Stream::InputStream& stream, bool transparent, ImageOut& output);
 
 	BitmapHeader ParseHeader(const uint8_t*& ptr, uint8_t const* e);
 }

diff --git a/src/image_png.cpp b/src/image_png.cpp
@@ -47,26 +47,23 @@ static void on_png_error(png_structp, png_const_charp error_msg) {
 	Output::Warning("libpng: {}", error_msg);
 }
 
-static bool ReadPNGWithReadFunction(png_voidp,png_rw_ptr, bool, int&, int&, void*&);
+static bool ReadPNGWithReadFunction(png_voidp,png_rw_ptr, bool, ImageOut&);
 static void ReadPalettedData(png_struct*, png_info*, png_uint_32, png_uint_32, bool, uint32_t*);
 static void ReadGrayData(png_struct*, png_info*, png_uint_32, png_uint_32, bool, uint32_t*);
 static void ReadGrayAlphaData(png_struct*, png_info*, png_uint_32, png_uint_32, uint32_t*);
 static void ReadRGBData(png_struct*, png_info*, png_uint_32, png_uint_32, uint32_t*);
 static void ReadRGBAData(png_struct*, png_info*, png_uint_32, png_uint_32, uint32_t*);
 
-bool ImagePNG::ReadPNG(const void* buffer, bool transparent,
-	int& width, int& height, void*& pixels) {
-	return ReadPNGWithReadFunction((png_voidp)&buffer, read_data, transparent, width, height, pixels);
+bool ImagePNG::Read(const void* buffer, bool transparent, ImageOut& output) {
+	return ReadPNGWithReadFunction((png_voidp)&buffer, read_data, transparent, output);
 }
 
-bool ImagePNG::ReadPNG(Filesystem_Stream::InputStream& stream, bool transparent,
-	int& width, int& height, void*& pixels) {
-	return ReadPNGWithReadFunction(&stream, read_data_istream, transparent, width, height, pixels);
+bool ImagePNG::Read(Filesystem_Stream::InputStream& stream, bool transparent, ImageOut& output) {
+	return ReadPNGWithReadFunction(&stream, read_data_istream, transparent, output);
 }
 
-static bool ReadPNGWithReadFunction(png_voidp user_data, png_rw_ptr fn, bool transparent,
-					   int& width, int& height, void*& pixels) {
-	pixels = nullptr;
+static bool ReadPNGWithReadFunction(png_voidp user_data, png_rw_ptr fn, bool transparent, ImageOut& output) {
+	output.pixels = nullptr;
 
 	png_struct *png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, on_png_error, on_png_warning);
 	if (png_ptr == NULL) {
@@ -94,35 +91,40 @@ static bool ReadPNGWithReadFunction(png_voidp user_data, png_rw_ptr fn, bool tra
 	png_get_IHDR(png_ptr, info_ptr, &w, &h,
 				 &bit_depth, &color_type, NULL, NULL, NULL);
 
-	pixels = malloc(w * h * 4);
-	if (!pixels) {
+	output.pixels = malloc(w * h * 4);
+	if (!output.pixels) {
 		Output::Warning("Error allocating PNG pixel buffer.");
 		return false;
 	}
 
 	switch (color_type) {
 		case PNG_COLOR_TYPE_PALETTE:
-			ReadPalettedData(png_ptr, info_ptr, w, h, transparent, (uint32_t*)pixels);
+			ReadPalettedData(png_ptr, info_ptr, w, h, transparent, (uint32_t*)output.pixels);
+			output.bpp = 8;
 			break;
 		case PNG_COLOR_TYPE_GRAY:
-			ReadGrayData(png_ptr, info_ptr, w, h, transparent, (uint32_t*)pixels);
+			ReadGrayData(png_ptr, info_ptr, w, h, transparent, (uint32_t*)output.pixels);
+			output.bpp = 8;
 			break;
 		case PNG_COLOR_TYPE_GRAY_ALPHA:
-			ReadGrayAlphaData(png_ptr, info_ptr, w, h, (uint32_t*)pixels);
+			ReadGrayAlphaData(png_ptr, info_ptr, w, h, (uint32_t*)output.pixels);
+			output.bpp = 8;
 			break;
 		case PNG_COLOR_TYPE_RGB:
-			ReadRGBData(png_ptr, info_ptr, w, h, (uint32_t*)pixels);
+			ReadRGBData(png_ptr, info_ptr, w, h, (uint32_t*)output.pixels);
+			output.bpp = 24;
 			break;
 		case PNG_COLOR_TYPE_RGB_ALPHA:
-			ReadRGBAData(png_ptr, info_ptr, w, h, (uint32_t*)pixels);
+			ReadRGBAData(png_ptr, info_ptr, w, h, (uint32_t*)output.pixels);
+			output.bpp = 32;
 			break;
 	}
 
 	png_read_end(png_ptr, NULL);
 	png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
 
-	width = w;
-	height = h;
+	output.width = w;
+	output.height = h;
 	return true;
 }
 
@@ -251,7 +253,7 @@ static void flush_stream(png_structp out_ptr) {
 	reinterpret_cast<Filesystem_Stream::OutputStream*>(png_get_io_ptr(out_ptr))->flush();
 }
 
-bool ImagePNG::WritePNG(std::ostream& os, uint32_t width, uint32_t height, uint32_t* data) {
+bool ImagePNG::Write(std::ostream& os, uint32_t width, uint32_t height, uint32_t* data) {
 	png_structp write = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
 	if (!write) {
 		Output::Warning("Bitmap::WritePNG: error in png_create_write");

diff --git a/src/image_png.h b/src/image_png.h
@@ -19,12 +19,13 @@
 #define EP_IMAGE_PNG_H
 
 #include <cstdint>
+#include "bitmap.h"
 #include "filesystem_stream.h"
 
 namespace ImagePNG {
-	bool ReadPNG(const void* buffer, bool transparent, int& width, int& height, void*& pixels);
-	bool ReadPNG(Filesystem_Stream::InputStream& is, bool transparent, int& width, int& height, void*& pixels);
-	bool WritePNG(std::ostream& os, uint32_t width, uint32_t height, uint32_t* data);
+	bool Read(const void* buffer, bool transparent, ImageOut& output);
+	bool Read(Filesystem_Stream::InputStream& is, bool transparent, ImageOut& output);
+	bool Write(std::ostream& os, uint32_t width, uint32_t height, uint32_t* data);
 }
 
 #endif
diff --git a/src/image_xyz.cpp b/src/image_xyz.cpp
@@ -24,9 +24,8 @@
 #include "output.h"
 #include "image_xyz.h"
 
-bool ImageXYZ::ReadXYZ(const uint8_t* data, unsigned len, bool transparent,
-					   int& width, int& height, void*& pixels) {
-	pixels = nullptr;
+bool ImageXYZ::Read(const uint8_t* data, unsigned len, bool transparent, ImageOut& output) {
+	output.pixels = nullptr;
 
 	if (len < 8) {
 		Output::Warning("Not a valid XYZ file.");
@@ -47,13 +46,13 @@ bool ImageXYZ::ReadXYZ(const uint8_t* data, unsigned len, bool transparent,
 	}
 	const uint8_t (*palette)[3] = (const uint8_t(*)[3]) &dst_buffer.front();
 
-	pixels = malloc(w * h * 4);
-	if (!pixels) {
+	output.pixels = malloc(w * h * 4);
+	if (!output.pixels) {
 		Output::Warning("Error allocating XYZ pixel buffer.");
 		return false;
 	}
 
-	uint8_t* dst = (uint8_t*) pixels;
+	uint8_t* dst = (uint8_t*) output.pixels;
 	const uint8_t* src = (const uint8_t*) &dst_buffer[768];
 	for (int y = 0; y < h; y++) {
 		for (int x = 0; x < w; x++) {
@@ -66,13 +65,14 @@ bool ImageXYZ::ReadXYZ(const uint8_t* data, unsigned len, bool transparent,
 		}
 	}
 
-	width = w;
-	height = h;
+	output.width = w;
+	output.height = h;
+	output.bpp = 8;
+
 	return true;
 }
 
-bool ImageXYZ::ReadXYZ(Filesystem_Stream::InputStream& stream, bool transparent,
-					   int& width, int& height, void*& pixels) {
+bool ImageXYZ::Read(Filesystem_Stream::InputStream& stream, bool transparent, ImageOut& output) {
 	std::vector<uint8_t> buffer = Utils::ReadStream(stream);
-	return ReadXYZ(&buffer.front(), (unsigned) buffer.size(), transparent, width, height, pixels);
+	return Read(&buffer.front(), (unsigned) buffer.size(), transparent, output);
 }
diff --git a/src/image_xyz.h b/src/image_xyz.h
@@ -20,11 +20,12 @@
 
 #include <cstdio>
 #include <cstdint>
+#include "bitmap.h"
 #include "filesystem_stream.h"
 
 namespace ImageXYZ {
-	bool ReadXYZ(const uint8_t* data, unsigned len, bool transparent, int& width, int& height, void*& pixels);
-	bool ReadXYZ(Filesystem_Stream::InputStream& stream, bool transparent, int& width, int& height, void*& pixels);
+	bool Read(const uint8_t* data, unsigned len, bool transparent, ImageOut& output);
+	bool Read(Filesystem_Stream::InputStream& stream, bool transparent, ImageOut& output);
 }
 
 #endif