/*! \brief Reads a TGA header.
* Reads the header block from a binary TGA file populating the referenced TGA structure.
* \param ctx Pointer to TGA binary file
* \param tga Pointer to TGA structure
* \return int 1 on sucess, -1 on failure
*/
int read_header_tga(gdIOCtx *ctx, oTga *tga) {
unsigned char header[18];
if (gdGetBuf(header, sizeof(header), ctx) < 18) {
fprintf(stderr, "fail to read header");
return -1;
}
tga->identsize = header[0];
tga->colormaptype = header[1];
tga->imagetype = header[2];
tga->colormapstart = header[3] + (header[4] << 8);
tga->colormaplength = header[5] + (header[6] << 8);
tga->colormapbits = header[7];
tga->xstart = header[8] + (header[9] << 8);
tga->ystart = header[10] + (header[11] << 8);
tga->width = header[12] + (header[13] << 8);
tga->height = header[14] + (header[15] << 8);
tga->bits = header[16];
tga->alphabits = header[17] & 0x0f;
tga->fliph = (header[17] & 0x10) ? 1 : 0;
tga->flipv = (header[17] & 0x20) ? 0 : 1;
#if DEBUG
printf("format bps: %i\n", tga->bits);
printf("flip h/v: %i / %i\n", tga->fliph, tga->flipv);
printf("alpha: %i\n", tga->alphabits);
printf("wxh: %i %i\n", tga->width, tga->height);
#endif
switch(tga->bits) {
case 8:
case 16:
case 24:
case 32:
break;
default:
fprintf(stderr, "bps %i not supported", tga->bits);
return -1;
break;
}
tga->ident = NULL;
if (tga->identsize > 0) {
tga->ident = (char *) gdMalloc(tga->identsize * sizeof(char));
if(tga->ident == NULL) {
return -1;
}
gdGetBuf( &( tga->ident ), tga->identsize, ctx );
}
return 1;
}
/*! \brief Reads a TGA header.
* Reads the header block from a binary TGA file populating the referenced TGA structure.
* \param ctx Pointer to TGA binary file
* \param tga Pointer to TGA structure
* \return int 1 on sucess, -1 on failure
*/
int read_header_tga(gdIOCtx *ctx, oTga *tga)
{
unsigned char header[18];
if (gdGetBuf(header, sizeof(header), ctx) < 18) {
gd_error("fail to read header");
return -1;
}
tga->identsize = header[0];
tga->colormaptype = header[1];
tga->imagetype = header[2];
tga->colormapstart = header[3] + (header[4] << 8);
tga->colormaplength = header[5] + (header[6] << 8);
tga->colormapbits = header[7];
tga->xstart = header[8] + (header[9] << 8);
tga->ystart = header[10] + (header[11] << 8);
tga->width = header[12] + (header[13] << 8);
tga->height = header[14] + (header[15] << 8);
tga->bits = header[16];
tga->alphabits = header[17] & 0x0f;
tga->fliph = (header[17] & 0x10) ? 1 : 0;
tga->flipv = (header[17] & 0x20) ? 0 : 1;
#if DEBUG
printf("format bps: %i\n", tga->bits);
printf("flip h/v: %i / %i\n", tga->fliph, tga->flipv);
printf("alpha: %i\n", tga->alphabits);
printf("wxh: %i %i\n", tga->width, tga->height);
#endif
if (!((tga->bits == TGA_BPP_24 && tga->alphabits == 0)
|| (tga->bits == TGA_BPP_32 && tga->alphabits == 8)))
{
gd_error_ex(GD_WARNING, "gd-tga: %u bits per pixel with %u alpha bits not supported\n",
tga->bits, tga->alphabits);
return -1;
}
tga->ident = NULL;
if (tga->identsize > 0) {
tga->ident = (char *) gdMalloc(tga->identsize * sizeof(char));
if(tga->ident == NULL) {
return -1;
}
gdGetBuf(tga->ident, tga->identsize, ctx);
}
return 1;
}
static int
_gd2ReadChunk (int offset, char *compBuf, int compSize, char *chunkBuf,
uLongf * chunkLen, gdIOCtx * in)
{
int zerr;
if (gdTell (in) != offset) {
GD2_DBG (printf ("Positioning in file to %d\n", offset));
gdSeek (in, offset);
} else {
GD2_DBG (printf ("Already Positioned in file to %d\n", offset));
};
/* Read and uncompress an entire chunk. */
GD2_DBG (printf ("Reading file\n"));
if (gdGetBuf (compBuf, compSize, in) != compSize) {
return FALSE;
};
GD2_DBG (printf
("Got %d bytes. Uncompressing into buffer of %d bytes\n", compSize,
*chunkLen));
zerr =
uncompress ((unsigned char *) chunkBuf, chunkLen,
(unsigned char *) compBuf, compSize);
if (zerr != Z_OK) {
GD2_DBG (printf ("Error %d from uncompress\n", zerr));
return FALSE;
};
GD2_DBG (printf ("Got chunk\n"));
return TRUE;
}
static void gdPngReadData (png_structp png_ptr, png_bytep data, png_size_t length)
{
int check;
check = gdGetBuf(data, length, (gdIOCtx *) png_get_io_ptr(png_ptr));
if (check != length) {
png_error(png_ptr, "Read Error: truncated data");
}
}
safeboolean
fill_input_buffer (j_decompress_ptr cinfo)
{
my_src_ptr src = (my_src_ptr) cinfo->src;
/* 2.0.12: signed size. Thanks to Geert Jansen */
/* 2.0.14: some platforms (mingw-msys) don't have ssize_t. Call
an int an int. */
int nbytes = 0;
memset (src->buffer, 0, INPUT_BUF_SIZE);
while (nbytes < INPUT_BUF_SIZE)
{
int got = gdGetBuf (src->buffer + nbytes,
INPUT_BUF_SIZE - nbytes,
src->infile);
if ((got == EOF) || (got == 0))
{
/* EOF or error. If we got any data, don't worry about it.
If we didn't, then this is unexpected. */
if (!nbytes)
{
nbytes = -1;
}
break;
}
nbytes += got;
}
if (nbytes <= 0)
{
if (src->start_of_file) /* Treat empty input file as fatal error */
ERREXIT (cinfo, JERR_INPUT_EMPTY);
WARNMS (cinfo, JWRN_JPEG_EOF);
/* Insert a fake EOI marker */
src->buffer[0] = (unsigned char) 0xFF;
src->buffer[1] = (unsigned char) JPEG_EOI;
nbytes = 2;
}
src->pub.next_input_byte = src->buffer;
src->pub.bytes_in_buffer = nbytes;
src->start_of_file = FALSE;
return TRUE;
}
/**
* int gdreadMRCHeader(gdIOCtx *io_ctx, MRCHeader *pMRCHeader)
*/
int gdreadMRCHeader(gdIOCtx *io_ctx, MRCHeader *pMRCHeader) {
gdGetBuf(pMRCHeader, MRC_HEADER_SIZE, io_ctx);
if( (pMRCHeader->nx < 0) || (pMRCHeader->ny < 0) ||
(pMRCHeader->nz < 0) || (pMRCHeader->mode < 0) ||
(pMRCHeader->mode > 4) || (pMRCHeader->x_length < 0) ||
(pMRCHeader->y_length < 0) || (pMRCHeader->z_length < 0) ||
(pMRCHeader->x_length > pMRCHeader->nx ) ||
(pMRCHeader->y_length > pMRCHeader->ny ) ||
(pMRCHeader->z_length > pMRCHeader->nz )
)
return -1; /* This is not a valid pMRCHeader header */
return 1 ;
}
/**
* int gdloadMRC(gdIOCtx *io_ctx, int in_length, MRC *pMRC)
*/
int gdloadMRC(gdIOCtx *io_ctx, int in_length, MRC *pMRC) {
unsigned int uElementSize = 0;
unsigned int uElements = 0;
if (gdreadMRCHeader(io_ctx, &(pMRC->header))==-1)
return -1;
uElements = pMRC->header.nx * pMRC->header.ny * pMRC->header.nz;
switch(pMRC->header.mode) {
case MRC_MODE_BYTE:
uElementSize = sizeof(char);
break;
case MRC_MODE_SHORT:
uElementSize = sizeof(short);
break;
case MRC_MODE_UNSIGNED_SHORT:
uElementSize = sizeof(short);
break;
case MRC_MODE_FLOAT:
uElementSize = sizeof(float);
break;
case MRC_MODE_SHORT_COMPLEX:
uElementSize = sizeof(short);
uElements *= 2;
break;
case MRC_MODE_FLOAT_COMPLEX:
uElementSize = sizeof(float);
uElements *= 2;
break;
default:
return -1;
}
if (in_length != (uElements*uElementSize+MRC_HEADER_SIZE))
return -1;
if((pMRC->pbyData = malloc(uElements*uElementSize)) == NULL)
pMRC->pbyData = malloc(uElements*uElementSize);
if(!gdGetBuf(pMRC->pbyData, (uElements*uElementSize), io_ctx))
return -1;
return 1;
}
/*! \brief Reads a TGA image data into buffer.
* Reads the image data block from a binary TGA file populating the referenced TGA structure.
* \param ctx Pointer to TGA binary file
* \param tga Pointer to TGA structure
* \return int 0 on sucess, -1 on failure
*/
int read_image_tga( gdIOCtx *ctx, oTga *tga )
{
int pixel_block_size = (tga->bits / 8);
int image_block_size = (tga->width * tga->height) * pixel_block_size;
uint8_t* decompression_buffer = NULL;
unsigned char* conversion_buffer = NULL;
int buffer_caret = 0;
int bitmap_caret = 0;
int i = 0;
int encoded_pixels;
if(overflow2(tga->width, tga->height)) {
return -1;
}
if(overflow2(tga->width * tga->height, pixel_block_size)) {
return -1;
}
if(overflow2(image_block_size, sizeof(int))) {
return -1;
}
/*! \todo Add more image type support.
*/
if (tga->imagetype != TGA_TYPE_RGB && tga->imagetype != TGA_TYPE_RGB_RLE)
return -1;
/*! \brief Allocate memmory for image block
* Allocate a chunk of memory for the image block to be passed into.
*/
tga->bitmap = (int *) gdMalloc(image_block_size * sizeof(int));
if (tga->bitmap == NULL)
return -1;
switch (tga->imagetype) {
case TGA_TYPE_RGB:
/*! \brief Read in uncompressed RGB TGA
* Chunk load the pixel data from an uncompressed RGB type TGA.
*/
conversion_buffer = (unsigned char *) gdMalloc(image_block_size * sizeof(unsigned char));
if (conversion_buffer == NULL) {
return -1;
}
if (gdGetBuf(conversion_buffer, image_block_size, ctx) != image_block_size) {
gd_error("gd-tga: premature end of image data\n");
gdFree(conversion_buffer);
return -1;
}
while (buffer_caret < image_block_size) {
tga->bitmap[buffer_caret] = (int) conversion_buffer[buffer_caret];
buffer_caret++;
}
gdFree(conversion_buffer);
break;
case TGA_TYPE_RGB_RLE:
/*! \brief Read in RLE compressed RGB TGA
* Chunk load the pixel data from an RLE compressed RGB type TGA.
*/
decompression_buffer = (uint8_t*) gdMalloc(image_block_size * sizeof(uint8_t));
if (decompression_buffer == NULL) {
return -1;
}
conversion_buffer = (unsigned char *) gdMalloc(image_block_size * sizeof(unsigned char));
if (conversion_buffer == NULL) {
gd_error("gd-tga: premature end of image data\n");
gdFree( decompression_buffer );
return -1;
}
if (gdGetBuf(conversion_buffer, image_block_size, ctx) != image_block_size) {
gdFree(conversion_buffer);
gdFree(decompression_buffer);
return -1;
}
buffer_caret = 0;
while( buffer_caret < image_block_size) {
decompression_buffer[buffer_caret] = (int)conversion_buffer[buffer_caret];
buffer_caret++;
}
buffer_caret = 0;
while( bitmap_caret < image_block_size ) {
if ((decompression_buffer[buffer_caret] & TGA_RLE_FLAG) == TGA_RLE_FLAG) {
encoded_pixels = ( ( decompression_buffer[ buffer_caret ] & ~TGA_RLE_FLAG ) + 1 );
buffer_caret++;
if ((bitmap_caret + (encoded_pixels * pixel_block_size)) >= image_block_size) {
gdFree( decompression_buffer );
gdFree( conversion_buffer );
return -1;
}
for (i = 0; i < encoded_pixels; i++) {
memcpy(tga->bitmap + bitmap_caret, decompression_buffer + buffer_caret, pixel_block_size);
bitmap_caret += pixel_block_size;
}
buffer_caret += pixel_block_size;
} else {
encoded_pixels = decompression_buffer[ buffer_caret ] + 1;
buffer_caret++;
if ((bitmap_caret + (encoded_pixels * pixel_block_size)) >= image_block_size) {
gdFree( decompression_buffer );
gdFree( conversion_buffer );
return -1;
}
memcpy(tga->bitmap + bitmap_caret, decompression_buffer + buffer_caret, encoded_pixels * pixel_block_size);
bitmap_caret += (encoded_pixels * pixel_block_size);
buffer_caret += (encoded_pixels * pixel_block_size);
}
}
gdFree( decompression_buffer );
gdFree( conversion_buffer );
break;
}
return 1;
}
/* This routine is based in part on the Chapter 13 demo code in "PNG: The
* Definitive Guide" (http://www.cdrom.com/pub/png/pngbook.html).
*/
gdImagePtr gdImageCreateFromPngCtx(gdIOCtx *infile)
{
png_byte sig[8];
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height, rowbytes;
int bit_depth, color_type, interlace_type;
int num_palette, num_trans;
png_colorp palette;
png_color_16p trans_gray_rgb;
png_bytep trans;
png_bytep image_data = NULL;
png_bytepp row_pointers = NULL;
gdImagePtr im = NULL;
int i, j, *open;
volatile int transparent = -1;
volatile int palette_allocated = FALSE;
/* Make sure the signature can't match by dumb luck -- TBB */
/* GRR: isn't sizeof(infile) equal to the size of the pointer? */
memset(infile, 0, sizeof(infile));
/* first do a quick check that the file really is a PNG image; could
* have used slightly more general png_sig_cmp() function instead */
gdGetBuf(sig, 8, infile);
if (!png_check_sig(sig, 8))
return NULL; /* bad signature */
#ifndef PNG_SETJMP_NOT_SUPPORTED
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, &gdPngJmpbufStruct,
gdPngErrorHandler, NULL);
#else
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
#endif
if (png_ptr == NULL) {
fprintf(stderr, "gd-png error: cannot allocate libpng main struct\n");
return NULL;
}
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
fprintf(stderr, "gd-png error: cannot allocate libpng info struct\n");
png_destroy_read_struct(&png_ptr, NULL, NULL);
return NULL;
}
/* we could create a second info struct here (end_info), but it's only
* useful if we want to keep pre- and post-IDAT chunk info separated
* (mainly for PNG-aware image editors and converters) */
/* setjmp() must be called in every non-callback function that calls a
* PNG-reading libpng function */
#ifndef PNG_SETJMP_NOT_SUPPORTED
if (setjmp(gdPngJmpbufStruct.jmpbuf)) {
fprintf(stderr, "gd-png error: setjmp returns error condition\n");
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
#endif
png_set_sig_bytes(png_ptr, 8); /* we already read the 8 signature bytes */
png_set_read_fn(png_ptr, (void *)infile, gdPngReadData);
png_read_info(png_ptr, info_ptr); /* read all PNG info up to image data */
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, NULL, NULL);
if (bit_depth == 16)
png_set_strip_16(png_ptr);
else if (bit_depth < 8)
png_set_packing(png_ptr); /* expand to 1 byte per pixel */
if (color_type & PNG_COLOR_MASK_ALPHA) {
fprintf(stderr, "gd-png warning: alpha channel not supported\n");
png_set_strip_alpha(png_ptr);
}
switch (color_type) {
case PNG_COLOR_TYPE_PALETTE:
png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette);
#ifdef DEBUG
fprintf(stderr, "gd-png color_type is palette, colors: %d\n",
num_palette);
#endif /* DEBUG */
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
int real_num_trans = 0, idx_first_trans = -1;
int min_trans = 256, idx_min_trans = -1;
png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, NULL);
for (i = 0; i < num_trans; ++i) {
if (trans[i] < 255) {
++real_num_trans;
if (idx_first_trans < 0)
idx_first_trans = i;
if (trans[i] < min_trans) {
min_trans = trans[i];
idx_min_trans = i;
}
}
}
if (real_num_trans > 0) {
if (real_num_trans > 1 || trans[idx_first_trans] != 0) {
fprintf(stderr, "gd-png warning: only single-color, "
"100%% transparency supported\n");
transparent = idx_min_trans;
} else {
transparent = idx_first_trans;
}
}
}
break;
case PNG_COLOR_TYPE_GRAY:
case PNG_COLOR_TYPE_GRAY_ALPHA:
/* create a fake palette and check for single-shade transparency */
if ((palette = (png_colorp)gdMalloc(256*sizeof(png_color))) == NULL) {
fprintf(stderr, "gd-png error: cannot allocate gray palette\n");
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
palette_allocated = TRUE;
if (bit_depth < 8)
{
num_palette = 1<<bit_depth;
for (i = 0; i < 256; ++i)
{
j = (255*i)/(num_palette-1);
palette[i].red = palette[i].green = palette[i].blue = j;
}
}
else
{
num_palette = 256;
for (i = 0; i < 256; ++i)
{
palette[i].red = palette[i].green = palette[i].blue = i;
}
}
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
png_get_tRNS(png_ptr, info_ptr, NULL, NULL, &trans_gray_rgb);
if (bit_depth == 16) /* png_set_strip_16() not yet in effect */
transparent = trans_gray_rgb->gray >> 8;
else
transparent = trans_gray_rgb->gray;
/* Note slight error in 16-bit case: up to 256 16-bit shades
* may get mapped to a single 8-bit shade, and only one of them
* is supposed to be transparent. IOW, both opaque pixels and
* transparent pixels will be mapped into the transparent entry.
* There is no particularly good way around this in the case
* that all 256 8-bit shades are used, but one could write some
* custom 16-bit code to handle the case where there are gdFree
* palette entries. This error will be extremely rare in
* general, though. (Quite possibly there is only one such
* image in existence.) */
}
break;
case PNG_COLOR_TYPE_RGB:
case PNG_COLOR_TYPE_RGB_ALPHA:
/* allocate a palette and check for single-shade transparency */
if ((palette = (png_colorp)gdMalloc(256*sizeof(png_color))) == NULL) {
fprintf(stderr, "gd-png error: cannot allocate RGB palette\n");
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
palette_allocated = TRUE;
num_palette = 256;
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
png_get_tRNS(png_ptr, info_ptr, NULL, NULL, &trans_gray_rgb);
if (bit_depth == 16) { /* png_set_strip_16() not yet active */
palette[0].red = trans_gray_rgb->red >> 8;
palette[0].green = trans_gray_rgb->green >> 8;
palette[0].blue = trans_gray_rgb->blue >> 8;
} else {
static void gdPngReadData(png_structp png_ptr,
png_bytep data, png_size_t length)
{
gdGetBuf(data, length, (gdIOCtx *)
png_get_io_ptr(png_ptr));
}
/* This routine is based in part on the Chapter 13 demo code in "PNG: The
* Definitive Guide" (http://www.cdrom.com/pub/png/pngbook.html).
*/
gdImagePtr gdImageCreateFromPngCtx (gdIOCtx * infile)
{
png_byte sig[8];
#ifdef PNG_SETJMP_SUPPORTED
jmpbuf_wrapper jbw;
#endif
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height, rowbytes, w, h;
int bit_depth, color_type, interlace_type;
int num_palette, num_trans;
png_colorp palette;
png_color_16p trans_gray_rgb;
png_color_16p trans_color_rgb;
png_bytep trans;
volatile png_bytep image_data = NULL;
volatile png_bytepp row_pointers = NULL;
gdImagePtr im = NULL;
int i, j, *open = NULL;
volatile int transparent = -1;
volatile int palette_allocated = FALSE;
/* Make sure the signature can't match by dumb luck -- TBB */
/* GRR: isn't sizeof(infile) equal to the size of the pointer? */
memset (sig, 0, sizeof(sig));
/* first do a quick check that the file really is a PNG image; could
* have used slightly more general png_sig_cmp() function instead
*/
if (gdGetBuf(sig, 8, infile) < 8) {
return NULL;
}
if (png_sig_cmp(sig, 0, 8) != 0) { /* bad signature */
return NULL;
}
#ifdef PNG_SETJMP_SUPPORTED
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, &jbw, gdPngErrorHandler, NULL);
#else
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
#endif
if (png_ptr == NULL) {
php_gd_error("gd-png error: cannot allocate libpng main struct");
return NULL;
}
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL) {
php_gd_error("gd-png error: cannot allocate libpng info struct");
png_destroy_read_struct (&png_ptr, NULL, NULL);
return NULL;
}
/* we could create a second info struct here (end_info), but it's only
* useful if we want to keep pre- and post-IDAT chunk info separated
* (mainly for PNG-aware image editors and converters)
*/
/* setjmp() must be called in every non-callback function that calls a
* PNG-reading libpng function
*/
#ifdef PNG_SETJMP_SUPPORTED
if (setjmp(jbw.jmpbuf)) {
php_gd_error("gd-png error: setjmp returns error condition");
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
#endif
png_set_sig_bytes(png_ptr, 8); /* we already read the 8 signature bytes */
png_set_read_fn(png_ptr, (void *) infile, gdPngReadData);
png_read_info(png_ptr, info_ptr); /* read all PNG info up to image data */
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL);
if ((color_type == PNG_COLOR_TYPE_RGB) || (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
|| color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
im = gdImageCreateTrueColor((int) width, (int) height);
} else {
im = gdImageCreate((int) width, (int) height);
}
if (im == NULL) {
php_gd_error("gd-png error: cannot allocate gdImage struct");
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
if (bit_depth == 16) {
png_set_strip_16(png_ptr);
} else if (bit_depth < 8) {
png_set_packing (png_ptr); /* expand to 1 byte per pixel */
}
/* setjmp() must be called in every non-callback function that calls a
* PNG-reading libpng function
*/
#ifdef PNG_SETJMP_SUPPORTED
if (setjmp(jbw.jmpbuf)) {
php_gd_error("gd-png error: setjmp returns error condition");
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
gdFree(image_data);
gdFree(row_pointers);
if (im) {
gdImageDestroy(im);
}
return NULL;
}
#endif
switch (color_type) {
case PNG_COLOR_TYPE_PALETTE:
png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette);
if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS)) {
/* gd 2.0: we support this rather thoroughly now. Grab the
* first fully transparent entry, if any, as the value of
* the simple-transparency index, mostly for backwards
* binary compatibility. The alpha channel is where it's
* really at these days.
*/
int firstZero = 1;
png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, NULL);
for (i = 0; i < num_trans; ++i) {
im->alpha[i] = gdAlphaMax - (trans[i] >> 1);
if ((trans[i] == 0) && (firstZero)) {
transparent = i;
firstZero = 0;
}
}
}
break;
case PNG_COLOR_TYPE_GRAY:
/* create a fake palette and check for single-shade transparency */
if ((palette = (png_colorp) gdMalloc (256 * sizeof (png_color))) == NULL) {
php_gd_error("gd-png error: cannot allocate gray palette");
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
palette_allocated = TRUE;
if (bit_depth < 8) {
num_palette = 1 << bit_depth;
for (i = 0; i < 256; ++i) {
j = (255 * i) / (num_palette - 1);
palette[i].red = palette[i].green = palette[i].blue = j;
}
} else {
num_palette = 256;
for (i = 0; i < 256; ++i) {
palette[i].red = palette[i].green = palette[i].blue = i;
}
}
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
png_get_tRNS(png_ptr, info_ptr, NULL, NULL, &trans_gray_rgb);
if (bit_depth == 16) { /* png_set_strip_16() not yet in effect */
transparent = trans_gray_rgb->gray >> 8;
} else {
transparent = trans_gray_rgb->gray;
}
/* Note slight error in 16-bit case: up to 256 16-bit shades
* may get mapped to a single 8-bit shade, and only one of them
* is supposed to be transparent. IOW, both opaque pixels and
* transparent pixels will be mapped into the transparent entry.
* There is no particularly good way around this in the case
* that all 256 8-bit shades are used, but one could write some
* custom 16-bit code to handle the case where there are gdFree
* palette entries. This error will be extremely rare in
* general, though. (Quite possibly there is only one such
* image in existence.)
*/
}
/*! \brief Reads a TGA image data into buffer.
* Reads the image data block from a binary TGA file populating the referenced TGA structure.
* \param ctx Pointer to TGA binary file
* \param tga Pointer to TGA structure
* \return int 0 on sucess, -1 on failure
*/
int read_image_tga( gdIOCtx *ctx, oTga *tga ) {
int pixel_block_size = (tga->bits / 8);
int image_block_size = (tga->width * tga->height) * pixel_block_size;
byte* decompression_buffer = NULL;
unsigned char* conversion_buffer = NULL;
int buffer_caret = 0;
int bitmap_caret = 0;
int i = 0;
int j = 0;
byte encoded_pixels;
if(overflow2(tga->width, tga->height)) {
return -1;
}
if(overflow2(tga->width * tga->height, pixel_block_size)) {
return -1;
}
if(overflow2(image_block_size, sizeof(byte))) {
return -1;
}
/*! \brief Allocate memmory for image block
* Allocate a chunk of memory for the image block to be passed into.
*/
tga->bitmap = (int *) gdMalloc(image_block_size * sizeof(byte));
if (tga->bitmap == NULL) {
return -1;
}
/*! \todo Add image type support
* Add support for this image type.
*/
if (tga->imagetype == TGA_TYPE_INDEXED) {
return -1;
}
/*! \todo Add image type support
* Add support for this image type.
*/
if (tga->imagetype == TGA_TYPE_INDEXED_RLE) {
return -1;
}
/*! \brief Read in uncompressed RGB TGA
* Chunk load the pixel data from an uncompressed RGB type TGA.
*/
if (tga->imagetype == TGA_TYPE_RGB) {
conversion_buffer = (unsigned char *) gdMalloc(image_block_size * sizeof(unsigned char));
if (conversion_buffer == NULL) {
gdFree(conversion_buffer);
return -1;
}
gdGetBuf(conversion_buffer, image_block_size, ctx);
while (buffer_caret < image_block_size) {
tga->bitmap[buffer_caret] = (int) conversion_buffer[buffer_caret];
buffer_caret++;
}
gdFree( conversion_buffer );
}
/*! \brief Read in RLE compressed RGB TGA
* Chunk load the pixel data from an RLE compressed RGB type TGA.
*/
if (tga->imagetype == TGA_TYPE_RGB_RLE) {
decompression_buffer = (byte*) gdMalloc(image_block_size * sizeof(byte));
if (decompression_buffer == NULL) {
gdFree( decompression_buffer );
return -1;
}
conversion_buffer = (unsigned char *) gdMalloc(image_block_size * sizeof(unsigned char));
if (conversion_buffer == NULL) {
gdFree( decompression_buffer );
gdFree( conversion_buffer );
return -1;
}
gdGetBuf( conversion_buffer, image_block_size, ctx );
buffer_caret = 0;
while( buffer_caret < image_block_size ) {
decompression_buffer[buffer_caret] = (int)conversion_buffer[buffer_caret];
buffer_caret++;
}
buffer_caret = 0;
while( bitmap_caret < image_block_size ) {
if ((decompression_buffer[buffer_caret] & TGA_RLE_FLAG) == TGA_RLE_FLAG) {
encoded_pixels = ( ( decompression_buffer[ buffer_caret ] & 127 ) + 1 );
buffer_caret++;
for (i = 0; i < encoded_pixels; i++) {
for (j = 0; j < pixel_block_size; j++, bitmap_caret++) {
tga->bitmap[ bitmap_caret ] = decompression_buffer[ buffer_caret + j ];
}
}
buffer_caret += pixel_block_size;
} else {
encoded_pixels = decompression_buffer[ buffer_caret ] + 1;
buffer_caret++;
for (i = 0; i < encoded_pixels; i++) {
for( j = 0; j < pixel_block_size; j++, bitmap_caret++ ) {
tga->bitmap[ bitmap_caret ] = decompression_buffer[ buffer_caret + j ];
}
buffer_caret += pixel_block_size;
}
}
}
gdFree( decompression_buffer );
gdFree( conversion_buffer );
}
/*! \todo Add image type support
* Add support for this image type.
*/
if( tga->imagetype == TGA_TYPE_GREYSCALE ) {
return -1;
}
/*! \todo Add image type support
* Add support for this image type.
*/
if( tga->imagetype == TGA_TYPE_GREYSCALE_RLE ) {
return -1;
}
return 0;
}
