bluecore/corona/src/OpenBMP.cpp

679 lines
19 KiB
C++

// format information gleaned from
// http://www.daubnet.com/formats/BMP.html
// and
// http://www.edm2.com/0107/os2bmp.html
//
// If you have Visual Studio.NET:
// ms-help://MS.VSCC/MS.MSDNVS/gdi/bitmaps_7c36.htm
#include <string.h>
#include "corona.h"
#include "SimpleImage.h"
#include "Utility.h"
namespace corona {
struct Header {
bool os2;
int file_size;
int data_offset;
int width;
int height;
int bpp;
int compression;
int pitch; // number of bytes in each scanline
int image_size;
auto_array<BGR> palette;
int palette_size;
// for bitfield specification...
// /*- 16-bit only -*/
u32 bf_red_mask, bf_red_shift, bf_red_rshift;
u32 bf_green_mask, bf_green_shift, bf_green_rshift;
u32 bf_blue_mask, bf_blue_shift, bf_blue_rshift;
};
bool ReadHeader(File* file, Header& h);
bool ReadInfoHeader(File* file, Header& h);
bool ReadPalette(File* file, Header& h);
Image* DecodeBitmap(File* file, const Header& h);
Image* OpenBMP(File* file) {
Header h;
if (ReadHeader(file, h) &&
ReadInfoHeader(file, h) &&
ReadPalette(file, h)) {
return DecodeBitmap(file, h);
} else {
return 0;
}
}
bool ReadHeader(File* file, Header& h) {
byte header[14];
if (file->read(header, 14) != 14) {
return false;
}
// check signature
if (header[0] != 'B' || header[1] != 'M') {
return false;
}
h.file_size = read32_le(header + 2);
h.data_offset = read32_le(header + 10);
return true;
}
bool ReadInfoHeader(File* file, Header& h) {
const int HEADER_READ_SIZE = 24;
// read the only part of the header we need
byte header[HEADER_READ_SIZE];
if (file->read(header, HEADER_READ_SIZE) != HEADER_READ_SIZE) {
return false;
}
int size = read32_le(header + 0);
int width;
int height;
int planes;
int bpp;
int compression;
int image_size;
if (size < 40) { // assume OS/2 bitmap
if (size < 12) {
return false;
}
h.os2 = true;
width = read16_le(header + 4);
height = read16_le(header + 6);
planes = read16_le(header + 8);
bpp = read16_le(header + 10);
compression = 0;
image_size = 0;
} else {
h.os2 = false;
width = read32_le(header + 4);
height = read32_le(header + 8);
planes = read16_le(header + 12);
bpp = read16_le(header + 14);
compression = read32_le(header + 16);
image_size = read32_le(header + 20);
}
// sanity check the info header
if (planes != 1) {
return false;
}
// adjust image_size
// (if compression == 0 or 3, manually calculate image size)
int line_size = 0;
if (compression == 0 || compression == 3) {
line_size = (width * bpp + 7) / 8;
line_size = (line_size + 3) / 4 * 4; // 32-bit-aligned
image_size = line_size * height;
}
h.width = width;
h.height = height;
h.bpp = bpp;
h.compression = compression;
h.pitch = line_size;
h.image_size = image_size;
// jump forward (backward in the OS/2 case :) to the palette data
file->seek(size - HEADER_READ_SIZE, File::CURRENT);
return true;
}
// count the number of consecutive zeroes on the right side of a
// binary number
// 0x00F0 will return 4
int count_right_zeroes(u32 n) {
int total = 0;
u32 c = 1;
while ((total < 32) && ((n & c) == 0)) {
c <<= 1;
++total;
}
return total;
}
// count the number of ones in a binary number
// 0x00F1 will return 5
int count_ones(u32 n) {
int total = 0;
u32 c = 1;
for (int i = 0; i < 32; ++i) {
if (n & c) {
++total;
}
c <<= 1;
}
return total;
}
bool ReadPalette(File* file, Header& h) {
// initialize bit masks/shifts... just in case
h.bf_red_mask = h.bf_red_shift = h.bf_red_rshift = 0;
h.bf_green_mask = h.bf_green_shift = h.bf_green_rshift = 0;
h.bf_blue_mask = h.bf_blue_shift = h.bf_blue_rshift = 0;
// if we're not a palettized image, don't even read a palette
if (h.bpp > 8) {
h.palette_size = 0;
// do we have bitfields?
if (h.compression == 3) {
auto_array<byte> bitfields(new byte[12]);
if (file->read(bitfields, 12) != 12) {
return false;
}
h.bf_red_mask = read32_le((byte*)bitfields);
h.bf_green_mask = read32_le((byte*)bitfields + 4);
h.bf_blue_mask = read32_le((byte*)bitfields + 8);
// calculate shifts
h.bf_red_shift = count_right_zeroes(h.bf_red_mask);
h.bf_green_shift = count_right_zeroes(h.bf_green_mask);
h.bf_blue_shift = count_right_zeroes(h.bf_blue_mask);
h.bf_red_rshift = 8 - count_ones(h.bf_red_mask);
h.bf_green_rshift = 8 - count_ones(h.bf_green_mask);
h.bf_blue_rshift = 8 - count_ones(h.bf_blue_mask);
// otherwise, set default bitfield entries
} else {
if (h.bpp == 16) {
h.bf_red_mask = 0x7C00;
h.bf_red_shift = 10;
h.bf_red_rshift = 3;
h.bf_green_mask = 0x03E0;
h.bf_green_shift = 5;
h.bf_green_rshift = 3;
h.bf_blue_mask = 0x001F;
h.bf_blue_shift = 0;
h.bf_blue_rshift = 3;
} else if (h.bpp == 32) {
// these don't need any rshift
h.bf_red_mask = 0x00FF0000; h.bf_red_shift = 16;
h.bf_green_mask = 0x0000FF00; h.bf_green_shift = 8;
h.bf_blue_mask = 0x000000FF; h.bf_blue_shift = 0;
}
}
return true;
}
if (h.bpp <= 8) {
h.palette_size = 1 << h.bpp;
} else {
h.palette_size = 0;
return true;
}
h.palette = new BGR[h.palette_size];
// read the BMP color table
const int buffer_size = h.palette_size * (h.os2 ? 3 : 4);
auto_array<byte> buffer(new byte[buffer_size]);
if (file->read(buffer, buffer_size) != buffer_size) {
return false;
}
byte* in = buffer;
BGR* out = h.palette;
for (int i = 0; i < h.palette_size; ++i) {
out->blue = *in++;
out->green = *in++;
out->red = *in++;
if (!h.os2) {
++in; // skip alpha
}
++out;
}
return true;
}
bool advance(int& x, int& y, const Header& h) {
if (++x >= h.width) {
x = 0;
if (++y >= h.height) {
return false;
}
}
return true;
}
Image* ReadBitmap1(const byte* raster_data, const Header& h) {
auto_array<byte> pixels(new byte[h.width * h.height]);
auto_array<BGR> palette(new BGR[256]);
memset(palette, 0, 256 * sizeof(BGR));
memcpy(palette, h.palette, h.palette_size * sizeof(BGR));
for (int i = 0; i < h.height; ++i) {
const byte* in = raster_data + i * h.pitch;
byte* out = pixels + (h.height - i - 1) * h.width;
int mask = 128;
for (int j = 0; j < h.width; ++j) {
*out++ = (*in & mask) > 0;
mask >>= 1;
if (mask == 0) {
++in;
mask = 128;
}
}
}
return new SimpleImage(h.width, h.height, PF_I8, pixels.release(),
(byte*)palette.release(), 256, PF_B8G8R8);
}
Image* ReadBitmap4(const byte* raster_data, const Header& h) {
auto_array<byte> pixels(new byte[h.width * h.height]);
auto_array<BGR> palette(new BGR[256]);
memset(palette, 0, 256 * sizeof(BGR));
memcpy(palette, h.palette, h.palette_size * sizeof(BGR));
for (int i = 0; i < h.height; ++i) {
const byte* in = raster_data + i * h.pitch;
byte* out = pixels + (h.height - i - 1) * h.width;
for (int j = 0; j < h.width / 2; ++j) {
*out++ = (*in >> 4);
*out++ = (*in & 0x0F);
++in;
}
if (h.width % 2) {
*out++ = (*in >> 4);
}
}
return new SimpleImage(h.width, h.height, PF_I8, pixels.release(),
(byte*)palette.release(), 256, PF_B8G8R8);
}
Image* ReadBitmapRLE4(const byte* raster_data, const Header& h) {
auto_array<byte> pixels(new byte[h.width * h.height]);
auto_array<BGR> palette(new BGR[256]);
memset(palette, 0, 256 * sizeof(BGR));
memcpy(palette, h.palette, h.palette_size * sizeof(BGR));
// by default, we have an empty bitmap
memset(pixels, 0, h.width * h.height);
// we read the image from the bottom down, and then flip it when
// we're done
int x = 0;
int y = 0;
const byte* in = raster_data;
while (in - raster_data < h.image_size - 1) {
byte n = *in++;
byte c = *in++;
if (n == 0) { // escape code
if (c == 0) { // end of line
x = 0;
//++y; // XXXaegis uhhh... uhhh... :) it works this way...
if (y >= h.height) {
// did we go too far?
break;
}
} else if (c == 1) { // end of bitmap
break;
} else if (c == 2) { // delta
// do we have enough space?
if (in - raster_data >= h.image_size - 1) {
break;
}
// I have no idea how I'm supposed to do this...
// Let's take a guess!
int dx = *in++;
int dy = *in++;
x = (x + dx) % h.width;
y += dy + (x + dx) / h.width;
if (y >= h.height) {
// if we went too far, stop now
break;
}
} else { // read uncompressed
// the input raster data is padded on DWORD boundaries
// c == num_pixels
int num_bytes = (c + 3) / 4 * 2;
// make sure we have enough space
if (in - raster_data > h.image_size - num_bytes) {
break;
}
// nasty decoding loop...
int i = 0;
int j = 0;
while (true) {
byte l = (in[j] & 0xF0) >> 4;
byte r = (in[j] & 0x0F);
++j;
pixels[y * h.width + x] = l;
if (!advance(x, y, h) || ++i >= c) {
break;
}
pixels[y * h.width + x] = r;
if (!advance(x, y, h) || ++i >= c) {
break;
}
}
// make SURE we move forward the right number of bytes
in += num_bytes;
}
} else {
// a less nasty decoding loop...
byte lc = (c & 0xF0) >> 4;
byte rc = c & 0x0F;
int i = 0;
while (true) {
pixels[y * h.width + x] = lc;
if (!advance(x, y, h) || ++i >= n) {
break;
}
pixels[y * h.width + x] = rc;
if (!advance(x, y, h) || ++i >= n) {
break;
}
}
} // end if
} // end while
// flippy flippy!
int pitch = h.width;
auto_array<byte> row(new byte[pitch]);
for (int i = 0; i < h.height / 2; ++i) {
int j = h.height - i - 1;
memcpy((byte*)row, pixels + i * pitch, pitch);
memcpy(pixels + i * pitch, pixels + j * pitch, pitch);
memcpy(pixels + j * pitch, (byte*)row, pitch);
}
return new SimpleImage(h.width, h.height, PF_I8, pixels.release(),
(byte*)palette.release(), 256, PF_B8G8R8);
}
Image* ReadBitmap8(const byte* raster_data, const Header& h) {
auto_array<byte> pixels(new byte[h.width * h.height]);
auto_array<BGR> palette(new BGR[256]);
memset(palette, 0, 256 * sizeof(BGR));
memcpy(palette, h.palette, h.palette_size * sizeof(BGR));
for (int i = 0; i < h.height; ++i) {
const byte* in = raster_data + i * h.pitch;
byte* out = pixels + (h.height - i - 1) * h.width;
for (int j = 0; j < h.width; ++j) {
*out++ = *in++;
}
}
return new SimpleImage(h.width, h.height, PF_I8, pixels.release(),
(byte*)palette.release(), 256, PF_B8G8R8);
}
Image* ReadBitmapRLE8(const byte* raster_data, const Header& h) {
auto_array<byte> pixels(new byte[h.width * h.height]);
auto_array<BGR> palette(new BGR[256]);
memset(palette, 0, 256 * sizeof(BGR));
memcpy(palette, h.palette, h.palette_size * sizeof(BGR));
// by default, we have an empty bitmap
memset(pixels, 0, h.width * h.height);
// we read the image from the bottom down, and then flip it when
// we're done
int x = 0;
int y = 0;
const byte* in = raster_data;
while (in - raster_data < h.image_size - 1) {
byte n = *in++;
byte c = *in++;
if (n == 0) { // escape code
if (c == 0) { // end of line
x = 0;
//++y; // XXXaegis uhhh... uhhh... :) it works this way...
if (y >= h.height) {
// did we go too far?
break;
}
} else if (c == 1) { // end of bitmap
break;
} else if (c == 2) { // delta
// do we have enough space?
if (in - raster_data >= h.image_size - 1) {
break;
}
// I have no idea how I'm supposed to do this...
// Let's take a guess!
int dx = *in++;
int dy = *in++;
x = (x + dx) % h.width;
y += dy + (x + dx) / h.width;
if (y >= h.height) {
// if we went too far, stop now
break;
}
} else { // read uncompressed
// c == num_pixels
int num_bytes = (c + 1) / 2 * 2;
// make sure we have enough space
if (in - raster_data > h.image_size - num_bytes) {
break;
}
// decoding loop...
int i = 0;
int j = 0;
while (true) {
pixels[y * h.width + x] = in[j++];
if (!advance(x, y, h) || ++i >= c) {
break;
}
}
// make SURE we move forward the right number of bytes
in += num_bytes;
}
} else {
int i = 0;
while (true) {
pixels[y * h.width + x] = c;
if (!advance(x, y, h) || ++i >= n) {
break;
}
}
} // end if
} // end while
// flippy flippy!
int pitch = h.width;
auto_array<byte> row(new byte[pitch]);
for (int i = 0; i < h.height / 2; ++i) {
int j = h.height - i - 1;
memcpy((byte*)row, pixels + i * pitch, pitch);
memcpy(pixels + i * pitch, pixels + j * pitch, pitch);
memcpy(pixels + j * pitch, (byte*)row, pitch);
}
return new SimpleImage(h.width, h.height, PF_I8, pixels.release(),
(byte*)palette.release(), 256, PF_B8G8R8);
}
Image* ReadBitmap16(const byte* raster_data, const Header& h) {
auto_array<RGB> pixels(new RGB[h.width * h.height]);
for (int i = 0; i < h.height; ++i) {
const byte* in = raster_data + i * h.pitch;
RGB* out = pixels + (h.height - i - 1) * h.width;
for (int j = 0; j < h.width; ++j) {
int clr = read16_le(in);
in += 2;
#define C16(C) \
(byte)( ((clr & h.bf_##C##_mask) >> h.bf_##C##_shift) << h.bf_##C##_rshift);
out->red = C16(red);
out->green = C16(green);
out->blue = C16(blue);
++out;
#undef C16
}
}
return new SimpleImage(h.width, h.height, PF_R8G8B8,
(byte*)pixels.release());
}
Image* ReadBitmap24(const byte* raster_data, const Header& h) {
auto_array<BGR> pixels(new BGR[h.width * h.height]);
for (int i = 0; i < h.height; ++i) {
const byte* in = raster_data + i * h.pitch;
BGR* out = pixels + (h.height - i - 1) * h.width;
for (int j = 0; j < h.width; ++j) {
out->blue = *in++;
out->green = *in++;
out->red = *in++;
++out;
}
}
return new SimpleImage(h.width, h.height, PF_B8G8R8,
(byte*)pixels.release());
}
Image* ReadBitmap32(const byte* raster_data, const Header& h) {
auto_array<RGB> pixels(new RGB[h.width * h.height]);
for (int i = 0; i < h.height; ++i) {
const byte* in = raster_data + i * h.pitch;
RGB* out = pixels + (h.height - i - 1) * h.width;
for (int j = 0; j < h.width; ++j) {
u32 pixel = read32_le(in);
in += 4;
out->red = (byte)((pixel & h.bf_red_mask) >> h.bf_red_shift);
out->green = (byte)((pixel & h.bf_green_mask) >> h.bf_green_shift);
out->blue = (byte)((pixel & h.bf_blue_mask) >> h.bf_blue_shift);
++out;
}
}
return new SimpleImage(h.width, h.height, PF_R8G8B8,
(byte*)pixels.release());
}
Image* DecodeBitmap(File* file, const Header& h) {
if (!file->seek(h.data_offset, File::BEGIN)) {
return 0;
}
// the raster data stored in the file
auto_array<byte> raster_data(new byte[h.image_size]);
if (file->read(raster_data, h.image_size) != h.image_size) {
return 0;
}
// the output pixel buffer (parameter to new SimpleImage)
auto_array<byte> pixels(new byte[h.width * h.height * 3]);
typedef Image* (*Decoder)(const byte* raster_data, const Header& h);
Decoder decoder = 0;
if (h.bpp == 1 && h.compression == 0) { decoder = ReadBitmap1; }
else if (h.bpp == 4 && h.compression == 0) { decoder = ReadBitmap4; }
else if (h.bpp == 4 && h.compression == 2) { decoder = ReadBitmapRLE4; }
else if (h.bpp == 8 && h.compression == 0) { decoder = ReadBitmap8; }
else if (h.bpp == 8 && h.compression == 1) { decoder = ReadBitmapRLE8; }
else if (h.bpp == 16 && (h.compression == 0 ||
h.compression == 3)) { decoder = ReadBitmap16; }
else if (h.bpp == 24 && h.compression == 0) { decoder = ReadBitmap24; }
else if (h.bpp == 32 && (h.compression == 0 ||
h.compression == 3)) { decoder = ReadBitmap32; }
if (decoder) {
return decoder(raster_data.get(), h);
} else {
return 0;
}
}
}