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godot/thirdparty/basis_universal/encoder/apg_bmp.c

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basis_universal: Update to upstream commit from Apr 16, 2021 BinomialLLC/basis_universal@ba1c3e40f1d434ebaf9a167b44e9b11d2bf0f765.
2021-05-07 15:00:41 +00:00
/*
BMP File Reader/Writer Implementation
Anton Gerdelan
Version: 3
Licence: see apg_bmp.h
C99
*/
#ifdef _MSC_VER
#define _CRT_SECURE_NO_WARNINGS 1
#endif
#include "apg_bmp.h"
#include <assert.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* Maximum pixel dimensions of width or height of an image. Should accommodate max used in graphics APIs.
NOTE: 65536*65536 is the biggest number storable in 32 bits.
This needs to be multiplied by n_channels so actual memory indices are not uint32 but size_t to avoid overflow.
Note this will crash stb_image_write et al at maximum size which use 32bits, so reduce max size to accom. */
#define _BMP_MAX_DIMS 65536
#define _BMP_FILE_HDR_SZ 14
#define _BMP_MIN_DIB_HDR_SZ 40
#define _BMP_MIN_HDR_SZ ( _BMP_FILE_HDR_SZ + _BMP_MIN_DIB_HDR_SZ )
#define _BMP_MAX_IMAGE_FILE_SIZE (1024ULL*1024ULL*1024ULL)
#pragma pack( push, 1 ) // supported on GCC in addition to individual packing attribs
/* All BMP files, regardless of type, start with this file header */
typedef struct _bmp_file_header_t {
char file_type[2];
uint32_t file_sz;
uint16_t reserved1;
uint16_t reserved2;
uint32_t image_data_offset;
} _bmp_file_header_t;
/* Following the file header is the BMP type header. this is the most commonly used format */
typedef struct _bmp_dib_BITMAPINFOHEADER_t {
uint32_t this_header_sz;
int32_t w; // in older headers w & h these are shorts and may be unsigned
int32_t h; //
uint16_t n_planes; // must be 1
uint16_t bpp; // bits per pixel. 1,4,8,16,24,32.
uint32_t compression_method; // 16 and 32-bit images must have a value of 3 here
uint32_t image_uncompressed_sz; // not consistently used in the wild, so ignored here.
int32_t horiz_pixels_per_meter; // not used.
int32_t vert_pixels_per_meter; // not used.
uint32_t n_colours_in_palette; //
uint32_t n_important_colours; // not used.
/* NOTE(Anton) a DIB header may end here at 40-bytes. be careful using sizeof() */
/* if 'compression' value, above, is set to 3 ie the image is 16 or 32-bit, then these colour channel masks follow the headers.
these are big-endian order bit masks to assign bits of each pixel to different colours. bits used must be contiguous and not overlap. */
uint32_t bitmask_r;
uint32_t bitmask_g;
uint32_t bitmask_b;
} _bmp_dib_BITMAPINFOHEADER_t;
#pragma pack( pop )
typedef enum _bmp_compression_t {
BI_RGB = 0,
BI_RLE8 = 1,
BI_RLE4 = 2,
BI_BITFIELDS = 3,
BI_JPEG = 4,
BI_PNG = 5,
BI_ALPHABITFIELDS = 6,
BI_CMYK = 11,
BI_CMYKRLE8 = 12,
BI_CMYRLE4 = 13
} _bmp_compression_t;
/* convenience struct and file->memory function */
typedef struct _entire_file_t {
void* data;
size_t sz;
} _entire_file_t;
/*
RETURNS
- true on success. record->data is allocated memory and must be freed by the caller.
- false on any error. Any allocated memory is freed if false is returned */
static bool _read_entire_file( const char* filename, _entire_file_t* record ) {
FILE* fp = fopen( filename, "rb" );
if ( !fp ) { return false; }
fseek( fp, 0L, SEEK_END );
record->sz = (size_t)ftell( fp );
// Immediately bail on anything larger than _BMP_MAX_IMAGE_FILE_SIZE.
if (record->sz > _BMP_MAX_IMAGE_FILE_SIZE) {
fclose( fp );
return false;
}
record->data = malloc( record->sz );
if ( !record->data ) {
fclose( fp );
return false;
}
rewind( fp );
size_t nr = fread( record->data, record->sz, 1, fp );
fclose( fp );
if ( 1 != nr ) { return false; }
return true;
}
static bool _validate_file_hdr( _bmp_file_header_t* file_hdr_ptr, size_t file_sz ) {
if ( !file_hdr_ptr ) { return false; }
if ( file_hdr_ptr->file_type[0] != 'B' || file_hdr_ptr->file_type[1] != 'M' ) { return false; }
if ( file_hdr_ptr->image_data_offset > file_sz ) { return false; }
return true;
}
static bool _validate_dib_hdr( _bmp_dib_BITMAPINFOHEADER_t* dib_hdr_ptr, size_t file_sz ) {
if ( !dib_hdr_ptr ) { return false; }
if ( _BMP_FILE_HDR_SZ + dib_hdr_ptr->this_header_sz > file_sz ) { return false; }
if ( ( 32 == dib_hdr_ptr->bpp || 16 == dib_hdr_ptr->bpp ) && ( BI_BITFIELDS != dib_hdr_ptr->compression_method && BI_ALPHABITFIELDS != dib_hdr_ptr->compression_method ) ) {
return false;
}
if ( BI_RGB != dib_hdr_ptr->compression_method && BI_BITFIELDS != dib_hdr_ptr->compression_method && BI_ALPHABITFIELDS != dib_hdr_ptr->compression_method ) {
return false;
}
// NOTE(Anton) using abs() in the if-statement was blowing up on large negative numbers. switched to labs()
if ( 0 == dib_hdr_ptr->w || 0 == dib_hdr_ptr->h || labs( dib_hdr_ptr->w ) > _BMP_MAX_DIMS || labs( dib_hdr_ptr->h ) > _BMP_MAX_DIMS ) { return false; }
/* NOTE(Anton) if images reliably used n_colours_in_palette we could have done a palette/file size integrity check here.
because some always set 0 then we have to check every palette indexing as we read them */
return true;
}
/* NOTE(Anton) this could have ifdef branches on different compilers for the intrinsics versions for perf */
static uint32_t _bitscan( uint32_t dword ) {
for ( uint32_t i = 0; i < 32; i++ ) {
if ( 1 & dword ) { return i; }
dword = dword >> 1;
}
return (uint32_t)-1;
}
unsigned char* apg_bmp_read( const char* filename, int* w, int* h, unsigned int* n_chans ) {
if ( !filename || !w || !h || !n_chans ) { return NULL; }
// read in the whole file into memory first - much faster than parsing on-the-fly
_entire_file_t record;
if ( !_read_entire_file( filename, &record ) ) { return NULL; }
if ( record.sz < _BMP_MIN_HDR_SZ ) {
free( record.data );
return NULL;
}
// grab and validate the first, file, header
_bmp_file_header_t* file_hdr_ptr = (_bmp_file_header_t*)record.data;
if ( !_validate_file_hdr( file_hdr_ptr, record.sz ) ) {
free( record.data );
return NULL;
}
// grad and validate the second, DIB, header
_bmp_dib_BITMAPINFOHEADER_t* dib_hdr_ptr = (_bmp_dib_BITMAPINFOHEADER_t*)( (uint8_t*)record.data + _BMP_FILE_HDR_SZ );
if ( !_validate_dib_hdr( dib_hdr_ptr, record.sz ) ) {
free( record.data );
return NULL;
}
// bitmaps can have negative dims to indicate the image should be flipped
uint32_t width = *w = abs( dib_hdr_ptr->w );
uint32_t height = *h = abs( dib_hdr_ptr->h );
// TODO(Anton) flip image memory at the end if this is true. because doing it per row was making me write bugs.
// bool vertically_flip = dib_hdr_ptr->h > 0 ? false : true;
// channel count and palette are not well defined in the header so we make a good guess here
uint32_t n_dst_chans = 3, n_src_chans = 3;
bool has_palette = false;
switch ( dib_hdr_ptr->bpp ) {
case 32: n_dst_chans = n_src_chans = 4; break; // technically can be RGB but not supported
case 24: n_dst_chans = n_src_chans = 3; break; // technically can be RGBA but not supported
case 8: // seems to always use a BGR0 palette, even for greyscale
n_dst_chans = 3;
has_palette = true;
n_src_chans = 1;
break;
case 4: // always has a palette - needed for a MS-saved BMP
n_dst_chans = 3;
has_palette = true;
n_src_chans = 1;
break;
case 1: // 1-bpp means the palette has 3 colour channels with 2 colours i.e. monochrome but not always black & white
n_dst_chans = 3;
has_palette = true;
n_src_chans = 1;
break;
default: // this includes 2bpp and 16bpp
free( record.data );
return NULL;
} // endswitch
*n_chans = n_dst_chans;
// NOTE(Anton) some image formats are not allowed a palette - could check for a bad header spec here also
if ( dib_hdr_ptr->n_colours_in_palette > 0 ) { has_palette = true; }
#ifdef APG_BMP_DEBUG_OUTPUT
printf( "apg_bmp_debug: reading image\n|-filename `%s`\n|-dims %ux%u pixels\n|-bpp %u\n|-n_src_chans %u\n|-n_dst_chans %u\n", filename, *w, *h,
dib_hdr_ptr->bpp, n_src_chans, n_dst_chans );
#endif
uint32_t palette_offset = _BMP_FILE_HDR_SZ + dib_hdr_ptr->this_header_sz;
bool has_bitmasks = false;
if ( BI_BITFIELDS == dib_hdr_ptr->compression_method || BI_ALPHABITFIELDS == dib_hdr_ptr->compression_method ) {
has_bitmasks = true;
palette_offset += 12;
}
if ( palette_offset > record.sz ) {
free( record.data );
return NULL;
}
// work out if any padding how much to skip at end of each row
uint32_t unpadded_row_sz = width * n_src_chans;
// bit-encoded palette indices have different padding properties
if ( 4 == dib_hdr_ptr->bpp ) {
unpadded_row_sz = width % 2 > 0 ? width / 2 + 1 : width / 2; // find how many whole bytes required for this bit width
}
if ( 1 == dib_hdr_ptr->bpp ) {
unpadded_row_sz = width % 8 > 0 ? width / 8 + 1 : width / 8; // find how many whole bytes required for this bit width
}
uint32_t row_padding_sz = 0 == unpadded_row_sz % 4 ? 0 : 4 - ( unpadded_row_sz % 4 ); // NOTE(Anton) didn't expect operator precedence of - over %
// another file size integrity check: partially validate source image data size
// 'image_data_offset' is by row padded to 4 bytes and is either colour data or palette indices.
if ( file_hdr_ptr->image_data_offset + ( unpadded_row_sz + row_padding_sz ) * height > record.sz ) {
free( record.data );
return NULL;
}
// find which bit number each colour channel starts at, so we can separate colours out
uint32_t bitshift_rgba[4] = {0, 0, 0, 0}; // NOTE(Anton) noticed this was int and not uint32_t so changed it. 17 Mar 2020
uint32_t bitmask_a = 0;
if ( has_bitmasks ) {
bitmask_a = ~( dib_hdr_ptr->bitmask_r | dib_hdr_ptr->bitmask_g | dib_hdr_ptr->bitmask_b );
bitshift_rgba[0] = _bitscan( dib_hdr_ptr->bitmask_r );
bitshift_rgba[1] = _bitscan( dib_hdr_ptr->bitmask_g );
bitshift_rgba[2] = _bitscan( dib_hdr_ptr->bitmask_b );
bitshift_rgba[3] = _bitscan( bitmask_a );
}
// allocate memory for the output pixels block. cast to size_t in case width and height are both the max of 65536 and n_dst_chans > 1
unsigned char* dst_img_ptr = malloc( (size_t)width * (size_t)height * (size_t)n_dst_chans );
if ( !dst_img_ptr ) {
free( record.data );
return NULL;
}
uint8_t* palette_data_ptr = (uint8_t*)record.data + palette_offset;
uint8_t* src_img_ptr = (uint8_t*)record.data + file_hdr_ptr->image_data_offset;
size_t dst_stride_sz = width * n_dst_chans;
// == 32-bpp -> 32-bit RGBA. == 32-bit and 16-bit require bitmasks
if ( 32 == dib_hdr_ptr->bpp ) {
// check source image has enough data in it to read from
if ( (size_t)file_hdr_ptr->image_data_offset + (size_t)height * (size_t)width * (size_t)n_src_chans > record.sz ) {
free( record.data );
free( dst_img_ptr );
return NULL;
}
size_t src_byte_idx = 0;
for ( uint32_t r = 0; r < height; r++ ) {
size_t dst_pixels_idx = r * dst_stride_sz;
for ( uint32_t c = 0; c < width; c++ ) {
uint32_t pixel;
memcpy( &pixel, &src_img_ptr[src_byte_idx], 4 );
// NOTE(Anton) the below assumes 32-bits is always RGBA 1 byte per channel. 10,10,10 RGB exists though and isn't handled.
dst_img_ptr[dst_pixels_idx++] = ( uint8_t )( ( pixel & dib_hdr_ptr->bitmask_r ) >> bitshift_rgba[0] );
dst_img_ptr[dst_pixels_idx++] = ( uint8_t )( ( pixel & dib_hdr_ptr->bitmask_g ) >> bitshift_rgba[1] );
dst_img_ptr[dst_pixels_idx++] = ( uint8_t )( ( pixel & dib_hdr_ptr->bitmask_b ) >> bitshift_rgba[2] );
dst_img_ptr[dst_pixels_idx++] = ( uint8_t )( ( pixel & bitmask_a ) >> bitshift_rgba[3] );
src_byte_idx += 4;
}
src_byte_idx += row_padding_sz;
}
// == 8-bpp -> 24-bit RGB ==
} else if ( 8 == dib_hdr_ptr->bpp && has_palette ) {
// validate indices (body of image data) fits in file
if ( file_hdr_ptr->image_data_offset + height * width > record.sz ) {
free( record.data );
free( dst_img_ptr );
return NULL;
}
size_t src_byte_idx = 0;
for ( uint32_t r = 0; r < height; r++ ) {
size_t dst_pixels_idx = ( height - 1 - r ) * dst_stride_sz;
for ( uint32_t c = 0; c < width; c++ ) {
// "most palettes are 4 bytes in RGB0 order but 3 for..." - it was actually BRG0 in old images -- Anton
uint8_t index = src_img_ptr[src_byte_idx]; // 8-bit index value per pixel
if ( palette_offset + index * 4 + 2 >= record.sz ) {
free( record.data );
return dst_img_ptr;
}
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[index * 4 + 2];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[index * 4 + 1];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[index * 4 + 0];
src_byte_idx++;
}
src_byte_idx += row_padding_sz;
}
// == 4-bpp (16-colour) -> 24-bit RGB ==
} else if ( 4 == dib_hdr_ptr->bpp && has_palette ) {
size_t src_byte_idx = 0;
for ( uint32_t r = 0; r < height; r++ ) {
size_t dst_pixels_idx = ( height - 1 - r ) * dst_stride_sz;
for ( uint32_t c = 0; c < width; c++ ) {
if ( file_hdr_ptr->image_data_offset + src_byte_idx > record.sz ) {
free( record.data );
free( dst_img_ptr );
return NULL;
}
// handle 2 pixels at a time
uint8_t pixel_duo = src_img_ptr[src_byte_idx];
uint8_t a_index = ( 0xFF & pixel_duo ) >> 4;
uint8_t b_index = 0xF & pixel_duo;
if ( palette_offset + a_index * 4 + 2 >= record.sz ) { // invalid src image
free( record.data );
return dst_img_ptr;
}
if ( dst_pixels_idx + 3 > width * height * n_dst_chans ) { // done
free( record.data );
return dst_img_ptr;
}
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[a_index * 4 + 2];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[a_index * 4 + 1];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[a_index * 4 + 0];
if ( ++c >= width ) { // advance a column
c = 0;
r++;
if ( r >= height ) { // done. no need to get second pixel. eg a 1x1 pixel image.
free( record.data );
return dst_img_ptr;
}
dst_pixels_idx = ( height - 1 - r ) * dst_stride_sz;
}
if ( palette_offset + b_index * 4 + 2 >= record.sz ) { // invalid src image
free( record.data );
return dst_img_ptr;
}
if ( dst_pixels_idx + 3 > width * height * n_dst_chans ) { // done. probably redundant check since checking r >= height.
free( record.data );
return dst_img_ptr;
}
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[b_index * 4 + 2];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[b_index * 4 + 1];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[b_index * 4 + 0];
src_byte_idx++;
}
src_byte_idx += row_padding_sz;
}
// == 1-bpp -> 24-bit RGB ==
} else if ( 1 == dib_hdr_ptr->bpp && has_palette ) {
/* encoding method for monochrome is not well documented.
a 2x2 pixel image is stored as 4 1-bit palette indexes
the palette is stored as any 2 RGB0 colours (not necessarily B&W)
so for an image with indexes like so:
1 1
0 1
it is bit-encoded as follows, starting at MSB:
01000000 00000000 00000000 00000000 (first byte val 64)
11000000 00000000 00000000 00000000 (first byte val 192)
data is still split by row and each row padded to 4 byte multiples
*/
size_t src_byte_idx = 0;
for ( uint32_t r = 0; r < height; r++ ) {
uint8_t bit_idx = 0; // used in monochrome
size_t dst_pixels_idx = ( height - 1 - r ) * dst_stride_sz;
for ( uint32_t c = 0; c < width; c++ ) {
if ( 8 == bit_idx ) { // start reading from the next byte
src_byte_idx++;
bit_idx = 0;
}
if ( file_hdr_ptr->image_data_offset + src_byte_idx > record.sz ) {
free( record.data );
return dst_img_ptr;
}
uint8_t pixel_oct = src_img_ptr[src_byte_idx];
uint8_t bit = 128 >> bit_idx;
uint8_t masked = pixel_oct & bit;
uint8_t palette_idx = masked > 0 ? 1 : 0;
if ( palette_offset + palette_idx * 4 + 2 >= record.sz ) {
free( record.data );
return dst_img_ptr;
}
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[palette_idx * 4 + 2];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[palette_idx * 4 + 1];
dst_img_ptr[dst_pixels_idx++] = palette_data_ptr[palette_idx * 4 + 0];
bit_idx++;
}
src_byte_idx += ( row_padding_sz + 1 ); // 1bpp is special here
}
// == 24-bpp -> 24-bit RGB == (but also should handle some other n_chans cases)
} else {
// NOTE(Anton) this only supports 1 byte per channel
if ( file_hdr_ptr->image_data_offset + height * width * n_dst_chans > record.sz ) {
free( record.data );
free( dst_img_ptr );
return NULL;
}
size_t src_byte_idx = 0;
for ( uint32_t r = 0; r < height; r++ ) {
size_t dst_pixels_idx = ( height - 1 - r ) * dst_stride_sz;
for ( uint32_t c = 0; c < width; c++ ) {
// re-orders from BGR to RGB
if ( n_dst_chans > 3 ) { dst_img_ptr[dst_pixels_idx++] = src_img_ptr[src_byte_idx + 3]; }
if ( n_dst_chans > 2 ) { dst_img_ptr[dst_pixels_idx++] = src_img_ptr[src_byte_idx + 2]; }
if ( n_dst_chans > 1 ) { dst_img_ptr[dst_pixels_idx++] = src_img_ptr[src_byte_idx + 1]; }
dst_img_ptr[dst_pixels_idx++] = src_img_ptr[src_byte_idx];
src_byte_idx += n_src_chans;
}
src_byte_idx += row_padding_sz;
}
} // endif bpp
free( record.data );
return dst_img_ptr;
}
void apg_bmp_free( unsigned char* pixels_ptr ) {
if ( !pixels_ptr ) { return; }
free( pixels_ptr );
}
unsigned int apg_bmp_write( const char* filename, unsigned char* pixels_ptr, int w, int h, unsigned int n_chans ) {
if ( !filename || !pixels_ptr ) { return 0; }
if ( 0 == w || 0 == h ) { return 0; }
if ( labs( w ) > _BMP_MAX_DIMS || labs( h ) > _BMP_MAX_DIMS ) { return 0; }
if ( n_chans != 3 && n_chans != 4 ) { return 0; }
uint32_t height = (uint32_t)labs( h );
uint32_t width = (uint32_t)labs( w );
// work out if any padding how much to skip at end of each row
const size_t unpadded_row_sz = width * n_chans;
const size_t row_padding_sz = 0 == unpadded_row_sz % 4 ? 0 : 4 - unpadded_row_sz % 4;
const size_t row_sz = unpadded_row_sz + row_padding_sz;
const size_t dst_pixels_padded_sz = row_sz * height;
const size_t dib_hdr_sz = sizeof( _bmp_dib_BITMAPINFOHEADER_t );
_bmp_file_header_t file_hdr;
{
file_hdr.file_type[0] = 'B';
file_hdr.file_type[1] = 'M';
file_hdr.file_sz = _BMP_FILE_HDR_SZ + (uint32_t)dib_hdr_sz + (uint32_t)dst_pixels_padded_sz;
file_hdr.reserved1 = 0;
file_hdr.reserved2 = 0;
file_hdr.image_data_offset = _BMP_FILE_HDR_SZ + (uint32_t)dib_hdr_sz;
}
_bmp_dib_BITMAPINFOHEADER_t dib_hdr;
{
dib_hdr.this_header_sz = _BMP_MIN_DIB_HDR_SZ; // NOTE: must be 40 and not include the bitmask memory in size here
dib_hdr.w = w;
dib_hdr.h = h;
dib_hdr.n_planes = 1;
dib_hdr.bpp = 3 == n_chans ? 24 : 32;
dib_hdr.compression_method = 3 == n_chans ? BI_RGB : BI_BITFIELDS;
dib_hdr.image_uncompressed_sz = 0;
dib_hdr.horiz_pixels_per_meter = 0;
dib_hdr.vert_pixels_per_meter = 0;
dib_hdr.n_colours_in_palette = 0;
dib_hdr.n_important_colours = 0;
// big-endian masks. only used in BI_BITFIELDS and BI_ALPHABITFIELDS ( 16 and 32-bit images )
// important note: GIMP stores BMP data in this array order for 32-bit: [A][B][G][R]
dib_hdr.bitmask_r = 0xFF000000;
dib_hdr.bitmask_g = 0x00FF0000;
dib_hdr.bitmask_b = 0x0000FF00;
}
uint8_t* dst_pixels_ptr = malloc( dst_pixels_padded_sz );
if ( !dst_pixels_ptr ) { return 0; }
{
size_t dst_byte_idx = 0;
uint8_t padding[4] = {0, 0, 0, 0};
uint8_t rgba[4] = {0, 0, 0, 0};
uint8_t bgra[4] = {0, 0, 0, 0};
for ( uint32_t row = 0; row < height; row++ ) {
size_t src_byte_idx = ( height - 1 - row ) * n_chans * width;
for ( uint32_t col = 0; col < width; col++ ) {
for ( uint32_t chan = 0; chan < n_chans; chan++ ) { rgba[chan] = pixels_ptr[src_byte_idx++]; }
if ( 3 == n_chans ) {
bgra[0] = rgba[2];
bgra[1] = rgba[1];
bgra[2] = rgba[0];
} else {
/* NOTE(Anton) RGBA with alpha channel would be better supported with an extended DIB header */
bgra[0] = rgba[3];
bgra[1] = rgba[2];
bgra[2] = rgba[1];
bgra[3] = rgba[0]; // alpha
}
memcpy( &dst_pixels_ptr[dst_byte_idx], bgra, n_chans );
dst_byte_idx += (size_t)n_chans;
} // endfor col
if ( row_padding_sz > 0 ) {
memcpy( &dst_pixels_ptr[dst_byte_idx], padding, row_padding_sz );
dst_byte_idx += row_padding_sz;
}
} // endfor row
}
{
FILE* fp = fopen( filename, "wb" );
if ( !fp ) {
free( dst_pixels_ptr );
return 0;
}
if ( 1 != fwrite( &file_hdr, _BMP_FILE_HDR_SZ, 1, fp ) ) {
free( dst_pixels_ptr );
fclose( fp );
return 0;
}
if ( 1 != fwrite( &dib_hdr, dib_hdr_sz, 1, fp ) ) {
free( dst_pixels_ptr );
fclose( fp );
return 0;
}
if ( 1 != fwrite( dst_pixels_ptr, dst_pixels_padded_sz, 1, fp ) ) {
free( dst_pixels_ptr );
fclose( fp );
return 0;
}
fclose( fp );
}
free( dst_pixels_ptr );
return 1;
}