terom@56: #ifndef PNGTILE_PNG_H
terom@56: #define PNGTILE_PNG_H
terom@56: 
terom@56: /**
terom@56:  * @file
terom@56:  * PNG-specific handling
terom@56:  */
terom@56: #include <png.h>
terom@56: #include <stdint.h>
terom@56: 
terom@56: /**
terom@56:  * Handle sparse data at this granularity (pixels)
terom@56:  */
terom@56: #define PT_IMG_BLOCK_SIZE 64
terom@56: 
terom@56: /**
terom@56:  * PNG img state
terom@56:  */
terom@56: struct pt_png_img {
terom@56:     /** libpng state */
terom@56:     png_struct *png;
terom@56:     png_info *info;
terom@56: 
terom@69:     /** Possible opened I/O file */
terom@69:     FILE *fh;
terom@56: };
terom@56: 
terom@56: /**
terom@56:  * Cache header layout for PNG-format images
terom@56:  */
terom@56: struct pt_png_header {
terom@56:     /** Pixel dimensions of image */
terom@56:     uint32_t width, height;
terom@56:     
terom@56:     /** Pixel format */
terom@56:     uint8_t bit_depth, color_type;
terom@56: 
terom@56:     /** Number of png_color entries that follow */
terom@56:     uint16_t num_palette;
terom@56: 
terom@56:     /** Number of bytes per row */
terom@56:     uint32_t row_bytes;
terom@56:     
terom@56:     /** Number of bytes per pixel */
terom@56:     uint8_t col_bytes;
terom@56: 
terom@56:     /** Palette entries, up to 256 entries used */
terom@56:     png_color palette[PNG_MAX_PALETTE_LENGTH];
terom@56: };
terom@56: 
terom@56: 
terom@56: #include "image.h"
terom@56: #include "tile.h"
terom@56: 
terom@69: /**
terom@69:  * Check if the given path looks like a .png file.
terom@69:  *
terom@69:  * Returns 0 if ok, 1 if non-png file, -1 on error
terom@69:  */
terom@69: int pt_png_check (const char *path);
terom@56: 
terom@56: /**
terom@56:  * Open the given .png image, and read info
terom@56:  */
terom@56: int pt_png_open (struct pt_image *image, struct pt_png_img *img);
terom@56: 
terom@56: /**
terom@56:  * Fill in the PNG header and return the size of the pixel data
terom@56:  */
terom@56: int pt_png_read_header (struct pt_png_img *img, struct pt_png_header *header, size_t *data_size);
terom@56: 
terom@56: /**
terom@56:  * Decode the PNG data into the given data segment, using the header as decoded by pt_png_read_header
terom@56:  */
terom@56: int pt_png_decode (struct pt_png_img *img, const struct pt_png_header *header, const struct pt_image_params *params, uint8_t *out);
terom@56: 
terom@56: /**
terom@56:  * Fill in img_* fields of pt_image_info from header
terom@56:  */
terom@56: int pt_png_info (struct pt_png_header *header, struct pt_image_info *info);
terom@56: 
terom@56: /**
terom@56:  * Render out a tile
terom@56:  */
terom@70: int pt_png_tile (const struct pt_png_header *header, const uint8_t *data, struct pt_tile *tile);
terom@56: 
terom@56: /**
terom@56:  * Release pt_png_ctx resources as allocated by pt_png_open
terom@56:  */
terom@56: void pt_png_release_read (struct pt_png_img *img);
terom@56: 
terom@56: /**
terom@56:  * Release pt_png_ctx resources as allocated by pt_png_...
terom@56:  */
terom@56: void pt_png_release_write (struct pt_png_img *img);
terom@56: 
terom@56: #endif