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682 lines
17 KiB
C
682 lines
17 KiB
C
/********************************************************************************************
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*
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* PNGU
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*
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* Original author: frontier (http://frontier-dev.net)
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* Modified by Tantric, 2009-2010
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*
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********************************************************************************************/
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#include <stdio.h>
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#include <malloc.h>
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#include <gccore.h>
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#include "pngu.h"
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#include <png.h>
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// Constants
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#define PNGU_SOURCE_BUFFER 1
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#define PNGU_SOURCE_DEVICE 2
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// Return codes
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#define PNGU_OK 0
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#define PNGU_ODD_WIDTH 1
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#define PNGU_ODD_STRIDE 2
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#define PNGU_INVALID_WIDTH_OR_HEIGHT 3
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#define PNGU_FILE_IS_NOT_PNG 4
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#define PNGU_UNSUPPORTED_COLOR_TYPE 5
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#define PNGU_NO_FILE_SELECTED 6
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#define PNGU_CANT_OPEN_FILE 7
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#define PNGU_CANT_READ_FILE 8
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#define PNGU_LIB_ERROR 9
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// Color types
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#define PNGU_COLOR_TYPE_GRAY 1
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#define PNGU_COLOR_TYPE_GRAY_ALPHA 2
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#define PNGU_COLOR_TYPE_PALETTE 3
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#define PNGU_COLOR_TYPE_RGB 4
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#define PNGU_COLOR_TYPE_RGB_ALPHA 5
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#define PNGU_COLOR_TYPE_UNKNOWN 6
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// PNGU Image context struct
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struct _IMGCTX
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{
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int source;
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void *buffer;
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char *filename;
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PNGU_u32 cursor;
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PNGU_u32 propRead;
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PNGUPROP prop;
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PNGU_u32 infoRead;
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png_structp png_ptr;
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png_infop info_ptr;
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FILE *fd;
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png_bytep *row_pointers;
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png_bytep img_data;
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};
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// PNGU Implementation
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static void pngu_free_info (IMGCTX ctx)
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{
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if (ctx->infoRead)
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{
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if (ctx->source == PNGU_SOURCE_DEVICE)
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fclose (ctx->fd);
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png_destroy_read_struct (&(ctx->png_ptr), &(ctx->info_ptr), (png_infopp)NULL);
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ctx->infoRead = 0;
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}
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}
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// Custom data provider function used for reading from memory buffers.
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static void pngu_read_data_from_buffer (png_structp png_ptr, png_bytep data, png_size_t length)
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{
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IMGCTX ctx = (IMGCTX) png_get_io_ptr (png_ptr);
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memcpy (data, ctx->buffer + ctx->cursor, length);
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ctx->cursor += length;
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}
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// Custom data writer function used for writing to memory buffers.
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static void pngu_write_data_to_buffer (png_structp png_ptr, png_bytep data, png_size_t length)
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{
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IMGCTX ctx = (IMGCTX) png_get_io_ptr (png_ptr);
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memcpy (ctx->buffer + ctx->cursor, data, length);
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ctx->cursor += length;
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}
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// Custom data flusher function used for writing to memory buffers.
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static void pngu_flush_data_to_buffer (png_structp png_ptr)
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{
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// Nothing to do here
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}
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static int pngu_info (IMGCTX ctx)
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{
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png_byte magic[8];
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png_uint_32 width;
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png_uint_32 height;
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png_color_16p background;
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png_bytep trans;
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png_color_16p trans_values;
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int scale, i;
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// Check if there is a file selected and if it is a valid .png
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if (ctx->source == PNGU_SOURCE_BUFFER)
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memcpy (magic, ctx->buffer, 8);
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else if (ctx->source == PNGU_SOURCE_DEVICE)
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{
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// Open file
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if (!(ctx->fd = fopen (ctx->filename, "rb")))
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return PNGU_CANT_OPEN_FILE;
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// Load first 8 bytes into magic buffer
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if (fread (magic, 1, 8, ctx->fd) != 8)
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{
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fclose (ctx->fd);
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return PNGU_CANT_READ_FILE;
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}
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}
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else
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return PNGU_NO_FILE_SELECTED;;
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if (png_sig_cmp(magic, 0, 8) != 0)
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{
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if (ctx->source == PNGU_SOURCE_DEVICE)
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fclose (ctx->fd);
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return PNGU_FILE_IS_NOT_PNG;
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}
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// Allocation of libpng structs
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ctx->png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
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if (!(ctx->png_ptr))
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{
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if (ctx->source == PNGU_SOURCE_DEVICE)
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fclose (ctx->fd);
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return PNGU_LIB_ERROR;
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}
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ctx->info_ptr = png_create_info_struct (ctx->png_ptr);
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if (!(ctx->info_ptr))
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{
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if (ctx->source == PNGU_SOURCE_DEVICE)
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fclose (ctx->fd);
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png_destroy_read_struct (&(ctx->png_ptr), (png_infopp)NULL, (png_infopp)NULL);
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return PNGU_LIB_ERROR;
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}
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if (ctx->source == PNGU_SOURCE_BUFFER)
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{
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// Installation of our custom data provider function
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ctx->cursor = 0;
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png_set_read_fn (ctx->png_ptr, ctx, pngu_read_data_from_buffer);
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}
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else if (ctx->source == PNGU_SOURCE_DEVICE)
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{
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// Default data provider uses function fread, so it needs to use our FILE*
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png_init_io (ctx->png_ptr, ctx->fd);
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png_set_sig_bytes (ctx->png_ptr, 8); // We have read 8 bytes already to check PNG authenticity
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}
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// Read png header
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png_read_info (ctx->png_ptr, ctx->info_ptr);
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// Query image properties if they have not been queried before
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if (!ctx->propRead)
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{
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int ctxNumTrans;
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png_get_IHDR(ctx->png_ptr, ctx->info_ptr, &width, &height,
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(int *) &(ctx->prop.imgBitDepth),
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(int *) &(ctx->prop.imgColorType),
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NULL, NULL, NULL);
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ctx->prop.imgWidth = width;
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ctx->prop.imgHeight = height;
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switch (ctx->prop.imgColorType)
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{
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case PNG_COLOR_TYPE_GRAY:
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ctx->prop.imgColorType = PNGU_COLOR_TYPE_GRAY;
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break;
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case PNG_COLOR_TYPE_GRAY_ALPHA:
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ctx->prop.imgColorType = PNGU_COLOR_TYPE_GRAY_ALPHA;
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break;
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case PNG_COLOR_TYPE_PALETTE:
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ctx->prop.imgColorType = PNGU_COLOR_TYPE_PALETTE;
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break;
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case PNG_COLOR_TYPE_RGB:
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ctx->prop.imgColorType = PNGU_COLOR_TYPE_RGB;
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break;
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case PNG_COLOR_TYPE_RGB_ALPHA:
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ctx->prop.imgColorType = PNGU_COLOR_TYPE_RGB_ALPHA;
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break;
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default:
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ctx->prop.imgColorType = PNGU_COLOR_TYPE_UNKNOWN;
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break;
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}
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// Constant used to scale 16 bit values to 8 bit values
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scale = 0;
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if (ctx->prop.imgBitDepth == 16)
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scale = 8;
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// Query background color, if any.
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ctx->prop.validBckgrnd = 0;
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switch(ctx->prop.imgColorType)
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{
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case PNGU_COLOR_TYPE_RGB:
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case PNGU_COLOR_TYPE_RGB_ALPHA:
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{
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if(png_get_bKGD (ctx->png_ptr, ctx->info_ptr, &background)){
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ctx->prop.validBckgrnd = 1;
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ctx->prop.bckgrnd.r = background->red >> scale;
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ctx->prop.bckgrnd.g = background->green >> scale;
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ctx->prop.bckgrnd.b = background->blue >> scale;
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}
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// Query list of transparent colors, if any.
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ctx->prop.numTrans = 0;
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ctx->prop.trans = NULL;
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if(png_get_tRNS (ctx->png_ptr, ctx->info_ptr, &trans, (int *) &(ctx->prop.numTrans), &trans_values)){
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ctxNumTrans = ctx->prop.numTrans;
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if(ctxNumTrans){
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ctx->prop.trans = malloc (sizeof (PNGUCOLOR) * ctxNumTrans);
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if (ctx->prop.trans)
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for (i = 0; i < ctxNumTrans; i++)
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{
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ctx->prop.trans[i].r = trans_values[i].red >> scale;
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ctx->prop.trans[i].g = trans_values[i].green >> scale;
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ctx->prop.trans[i].b = trans_values[i].blue >> scale;
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}
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else
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ctx->prop.numTrans = 0;
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}
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}
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}
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break;
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case PNGU_COLOR_TYPE_GRAY:
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case PNGU_COLOR_TYPE_GRAY_ALPHA:
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{
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if(png_get_bKGD (ctx->png_ptr, ctx->info_ptr, &background)){
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ctx->prop.validBckgrnd = 1;
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ctx->prop.bckgrnd.r =
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ctx->prop.bckgrnd.g =
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ctx->prop.bckgrnd.b = background->gray >> scale;
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}
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// Query list of transparent colors, if any.
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ctx->prop.numTrans = 0;
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ctx->prop.trans = NULL;
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if(png_get_tRNS (ctx->png_ptr, ctx->info_ptr, &trans, (int *) &(ctx->prop.numTrans), &trans_values)){
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ctxNumTrans = ctx->prop.numTrans;
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if(ctxNumTrans){
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ctx->prop.trans = malloc (sizeof (PNGUCOLOR) * ctxNumTrans);
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if (ctx->prop.trans)
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for (i = 0; i < ctxNumTrans; i++)
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ctx->prop.trans[i].r =
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ctx->prop.trans[i].g =
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ctx->prop.trans[i].b = trans_values[i].gray >> scale;
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else
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ctx->prop.numTrans = 0;
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}
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}
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}
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break;
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default:
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// It was none of those things,
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{
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// Query list of transparent colors, if any.
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ctx->prop.numTrans = 0;
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ctx->prop.trans = NULL;
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}
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break;
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}
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ctx->propRead = 1;
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}
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// Success
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ctx->infoRead = 1;
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return PNGU_OK;
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}
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static int pngu_decode (IMGCTX ctx, PNGU_u32 width, PNGU_u32 height, PNGU_u32 stripAlpha)
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{
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png_uint_32 rowbytes;
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png_uint_32 i, propImgHeight;
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// Read info if it hasn't been read before
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if (!ctx->infoRead)
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{
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int c = pngu_info (ctx);
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if (c != PNGU_OK)
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return c;
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}
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// Check if the user has specified the real width and height of the image
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if ( (ctx->prop.imgWidth != width) || (ctx->prop.imgHeight != height) )
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return PNGU_INVALID_WIDTH_OR_HEIGHT;
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// Check if color type is supported by PNGU
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if ( (ctx->prop.imgColorType == PNGU_COLOR_TYPE_PALETTE) || (ctx->prop.imgColorType == PNGU_COLOR_TYPE_UNKNOWN) )
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return PNGU_UNSUPPORTED_COLOR_TYPE;
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// Scale 16 bit samples to 8 bit
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if (ctx->prop.imgBitDepth == 16)
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png_set_strip_16 (ctx->png_ptr);
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// Remove alpha channel if we don't need it
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if (stripAlpha && ((ctx->prop.imgColorType == PNGU_COLOR_TYPE_RGB_ALPHA) || (ctx->prop.imgColorType == PNGU_COLOR_TYPE_GRAY_ALPHA)))
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png_set_strip_alpha (ctx->png_ptr);
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// Expand 1, 2 and 4 bit samples to 8 bit
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if (ctx->prop.imgBitDepth < 8)
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png_set_packing (ctx->png_ptr);
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// Transform grayscale images to RGB
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if ( (ctx->prop.imgColorType == PNGU_COLOR_TYPE_GRAY) || (ctx->prop.imgColorType == PNGU_COLOR_TYPE_GRAY_ALPHA) )
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png_set_gray_to_rgb (ctx->png_ptr);
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// Flush transformations
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png_read_update_info (ctx->png_ptr, ctx->info_ptr);
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// Allocate memory to store the image
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rowbytes = png_get_rowbytes (ctx->png_ptr, ctx->info_ptr);
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if (rowbytes & 3)
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rowbytes = ((rowbytes >> 2) + 1) << 2; // Add extra padding so each row starts in a 4 byte boundary
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ctx->img_data = malloc (rowbytes * ctx->prop.imgHeight);
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if (!ctx->img_data)
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{
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pngu_free_info (ctx);
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return PNGU_LIB_ERROR;
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}
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ctx->row_pointers = malloc (sizeof (png_bytep) * ctx->prop.imgHeight);
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if (!ctx->row_pointers)
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{
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free (ctx->img_data);
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pngu_free_info (ctx);
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return PNGU_LIB_ERROR;
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}
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propImgHeight = ctx->prop.imgHeight;
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for (i = 0; i < propImgHeight; ++i)
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ctx->row_pointers[i] = ctx->img_data + (i * rowbytes);
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// Transform the image and copy it to our allocated memory
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png_read_image (ctx->png_ptr, ctx->row_pointers);
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// Free resources
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pngu_free_info (ctx);
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// Success
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return PNGU_OK;
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}
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static inline PNGU_u32 coordsRGBA8(PNGU_u32 x, PNGU_u32 y, PNGU_u32 w)
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{
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return ((((y >> 2) * (w >> 2) + (x >> 2)) << 5) + ((y & 3) << 2) + (x & 3)) << 1;
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}
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static PNGU_u8 * PNGU_DecodeTo4x4RGBA8 (IMGCTX ctx, PNGU_u32 width, PNGU_u32 height, PNGU_u8 default_alpha)
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{
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PNGU_u8 *dst;
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PNGU_u32 x, y, offset;
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png_byte *pixel;
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if (pngu_decode (ctx, width, height, 0) != PNGU_OK)
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return NULL;
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PNGU_u32 newWidth = width;
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if(newWidth%4) newWidth += (4-newWidth%4);
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PNGU_u32 newHeight = height;
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if(newHeight%4) newHeight += (4-newHeight%4);
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int len = (newWidth * newHeight) << 2;
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if(len%32) len += (32-len%32);
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dst = memalign (32, len);
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if(!dst)
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return NULL;
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for (y = 0; y < newHeight; y++)
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{
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for (x = 0; x < newWidth; x++)
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{
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offset = coordsRGBA8(x, y, newWidth);
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if(y >= height || x >= width)
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{
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dst[offset] = 0;
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dst[offset+1] = 255;
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dst[offset+32] = 255;
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dst[offset+33] = 255;
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}
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else
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{
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if (ctx->prop.imgColorType == PNGU_COLOR_TYPE_GRAY_ALPHA ||
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ctx->prop.imgColorType == PNGU_COLOR_TYPE_RGB_ALPHA)
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{
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pixel = &(ctx->row_pointers[y][x*4]);
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dst[offset] = pixel[3]; // Alpha
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dst[offset+1] = pixel[0]; // Red
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dst[offset+32] = pixel[1]; // Green
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dst[offset+33] = pixel[2]; // Blue
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}
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else
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{
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pixel = &(ctx->row_pointers[y][x*3]);
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dst[offset] = default_alpha; // Alpha
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dst[offset+1] = pixel[0]; // Red
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dst[offset+32] = pixel[1]; // Green
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dst[offset+33] = pixel[2]; // Blue
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}
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}
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}
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}
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// Free resources
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free (ctx->img_data);
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free (ctx->row_pointers);
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DCFlushRange(dst, len);
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return dst;
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}
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IMGCTX PNGU_SelectImageFromBuffer (const void *buffer)
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{
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IMGCTX ctx = NULL;
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if (!buffer)
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return NULL;
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ctx = malloc (sizeof (struct _IMGCTX));
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if (!ctx)
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return NULL;
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ctx->buffer = (void *) buffer;
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ctx->source = PNGU_SOURCE_BUFFER;
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ctx->cursor = 0;
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ctx->filename = NULL;
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ctx->propRead = 0;
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ctx->infoRead = 0;
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return ctx;
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}
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IMGCTX PNGU_SelectImageFromDevice (const char *filename)
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{
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IMGCTX ctx = NULL;
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if (!filename)
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return NULL;
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ctx = malloc (sizeof (struct _IMGCTX));
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if (!ctx)
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return NULL;
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ctx->buffer = NULL;
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ctx->source = PNGU_SOURCE_DEVICE;
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ctx->cursor = 0;
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ctx->filename = malloc (strlen (filename) + 1);
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if (!ctx->filename)
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{
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free (ctx);
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return NULL;
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}
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strcpy(ctx->filename, filename);
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ctx->propRead = 0;
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ctx->infoRead = 0;
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return ctx;
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}
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void PNGU_ReleaseImageContext (IMGCTX ctx)
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{
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if (!ctx)
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return;
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if (ctx->filename)
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free (ctx->filename);
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if ((ctx->propRead) && (ctx->prop.trans))
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free (ctx->prop.trans);
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pngu_free_info (ctx);
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free (ctx);
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}
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int PNGU_GetImageProperties (IMGCTX ctx, PNGUPROP *imgprop)
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{
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int res;
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if (!ctx->propRead)
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{
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res = pngu_info (ctx);
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if (res != PNGU_OK)
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return res;
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}
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*imgprop = ctx->prop;
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return PNGU_OK;
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}
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PNGU_u8 * DecodePNG(const PNGU_u8 *src, int * width, int * height)
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{
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PNGUPROP imgProp;
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IMGCTX ctx = PNGU_SelectImageFromBuffer(src);
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PNGU_u8 *dst = NULL;
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if(!ctx)
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return NULL;
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if(PNGU_GetImageProperties(ctx, &imgProp) == PNGU_OK)
|
|
{
|
|
dst = PNGU_DecodeTo4x4RGBA8 (ctx, imgProp.imgWidth, imgProp.imgHeight, 255);
|
|
|
|
*width = imgProp.imgWidth;
|
|
*height = imgProp.imgHeight;
|
|
}
|
|
|
|
PNGU_ReleaseImageContext (ctx);
|
|
return dst;
|
|
}
|
|
|
|
int PNGU_EncodeFromRGB (IMGCTX ctx, PNGU_u32 width, PNGU_u32 height, void *buffer, PNGU_u32 stride)
|
|
{
|
|
png_uint_32 rowbytes;
|
|
PNGU_u32 y;
|
|
|
|
// Erase from the context any readed info
|
|
pngu_free_info (ctx);
|
|
ctx->propRead = 0;
|
|
|
|
// Check if the user has selected a file to write the image
|
|
if (ctx->source == PNGU_SOURCE_BUFFER);
|
|
|
|
else if (ctx->source == PNGU_SOURCE_DEVICE)
|
|
{
|
|
// Open file
|
|
if (!(ctx->fd = fopen (ctx->filename, "wb")))
|
|
return PNGU_CANT_OPEN_FILE;
|
|
}
|
|
|
|
else
|
|
return PNGU_NO_FILE_SELECTED;
|
|
|
|
// Allocation of libpng structs
|
|
ctx->png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
|
|
if (!(ctx->png_ptr))
|
|
{
|
|
if (ctx->source == PNGU_SOURCE_DEVICE)
|
|
fclose (ctx->fd);
|
|
return PNGU_LIB_ERROR;
|
|
}
|
|
|
|
ctx->info_ptr = png_create_info_struct (ctx->png_ptr);
|
|
if (!(ctx->info_ptr))
|
|
{
|
|
png_destroy_write_struct (&(ctx->png_ptr), (png_infopp)NULL);
|
|
if (ctx->source == PNGU_SOURCE_DEVICE)
|
|
fclose (ctx->fd);
|
|
return PNGU_LIB_ERROR;
|
|
}
|
|
|
|
if (ctx->source == PNGU_SOURCE_BUFFER)
|
|
{
|
|
// Installation of our custom data writer function
|
|
ctx->cursor = 0;
|
|
png_set_write_fn (ctx->png_ptr, ctx, pngu_write_data_to_buffer, pngu_flush_data_to_buffer);
|
|
}
|
|
else if (ctx->source == PNGU_SOURCE_DEVICE)
|
|
{
|
|
// Default data writer uses function fwrite, so it needs to use our FILE*
|
|
png_init_io (ctx->png_ptr, ctx->fd);
|
|
}
|
|
|
|
// Setup output file properties
|
|
png_set_IHDR (ctx->png_ptr, ctx->info_ptr, width, height, 8, PNG_COLOR_TYPE_RGB,
|
|
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
|
|
|
|
// Allocate memory to store the image in RGB format
|
|
rowbytes = width * 3;
|
|
if (rowbytes % 4)
|
|
rowbytes = ((rowbytes >>2) + 1) <<2; // Add extra padding so each row starts in a 4 byte boundary
|
|
|
|
ctx->img_data = malloc(rowbytes * height);
|
|
memset(ctx->img_data, 0, rowbytes * height);
|
|
|
|
if (!ctx->img_data)
|
|
{
|
|
png_destroy_write_struct (&(ctx->png_ptr), (png_infopp)NULL);
|
|
if (ctx->source == PNGU_SOURCE_DEVICE)
|
|
fclose (ctx->fd);
|
|
return PNGU_LIB_ERROR;
|
|
}
|
|
|
|
ctx->row_pointers = malloc (sizeof (png_bytep) * height);
|
|
memset(ctx->row_pointers, 0, sizeof (png_bytep) * height);
|
|
|
|
if (!ctx->row_pointers)
|
|
{
|
|
png_destroy_write_struct (&(ctx->png_ptr), (png_infopp)NULL);
|
|
if (ctx->source == PNGU_SOURCE_DEVICE)
|
|
fclose (ctx->fd);
|
|
return PNGU_LIB_ERROR;
|
|
}
|
|
|
|
for (y = 0; y < height; ++y)
|
|
{
|
|
ctx->row_pointers[y] = buffer + (y * rowbytes);
|
|
}
|
|
|
|
// Tell libpng where is our image data
|
|
png_set_rows (ctx->png_ptr, ctx->info_ptr, ctx->row_pointers);
|
|
|
|
// Write file header and image data
|
|
png_write_png (ctx->png_ptr, ctx->info_ptr, PNG_TRANSFORM_IDENTITY, NULL);
|
|
|
|
// Tell libpng we have no more data to write
|
|
png_write_end (ctx->png_ptr, (png_infop) NULL);
|
|
|
|
// Free resources
|
|
free (ctx->img_data);
|
|
free (ctx->row_pointers);
|
|
png_destroy_write_struct (&(ctx->png_ptr), &(ctx->info_ptr));
|
|
if (ctx->source == PNGU_SOURCE_DEVICE)
|
|
fclose (ctx->fd);
|
|
|
|
// Success
|
|
return ctx->cursor;
|
|
}
|
|
|
|
int PNGU_EncodeFromGXTexture (IMGCTX ctx, PNGU_u32 width, PNGU_u32 height, void *buffer, PNGU_u32 stride)
|
|
{
|
|
int res;
|
|
PNGU_u32 x,y, tmpy1, tmpy2, tmpyWid, tmpxy;
|
|
|
|
unsigned char * ptr = (unsigned char*)buffer;
|
|
unsigned char * tmpbuffer = (unsigned char *)malloc(width*height*3);
|
|
memset(tmpbuffer, 0, width*height*3);
|
|
png_uint_32 offset;
|
|
|
|
for(y=0; y < height; y++)
|
|
{
|
|
tmpy1 = y * 640*3;
|
|
tmpy2 = y%4 << 2;
|
|
tmpyWid = (((y >> 2)<<4)*width);
|
|
|
|
for(x=0; x < width; x++)
|
|
{
|
|
offset = tmpyWid + ((x >> 2)<<6) + ((tmpy2+ x%4 ) << 1);
|
|
tmpxy = x * 3 + tmpy1;
|
|
|
|
tmpbuffer[tmpxy ] = ptr[offset+1]; // R
|
|
tmpbuffer[tmpxy+1] = ptr[offset+32]; // G
|
|
tmpbuffer[tmpxy+2] = ptr[offset+33]; // B
|
|
}
|
|
}
|
|
|
|
res = PNGU_EncodeFromRGB (ctx, width, height, tmpbuffer, stride);
|
|
free(tmpbuffer);
|
|
return res;
|
|
}
|