image.h

00001 /*------------------------------------------------------------------------
00002  *  Copyright 2007-2009 (c) Jeff Brown <spadix@users.sourceforge.net>
00003  *
00004  *  This file is part of the ZBar Bar Code Reader.
00005  *
00006  *  The ZBar Bar Code Reader is free software; you can redistribute it
00007  *  and/or modify it under the terms of the GNU Lesser Public License as
00008  *  published by the Free Software Foundation; either version 2.1 of
00009  *  the License, or (at your option) any later version.
00010  *
00011  *  The ZBar Bar Code Reader is distributed in the hope that it will be
00012  *  useful, but WITHOUT ANY WARRANTY; without even the implied warranty
00013  *  of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014  *  GNU Lesser Public License for more details.
00015  *
00016  *  You should have received a copy of the GNU Lesser Public License
00017  *  along with the ZBar Bar Code Reader; if not, write to the Free
00018  *  Software Foundation, Inc., 51 Franklin St, Fifth Floor,
00019  *  Boston, MA  02110-1301  USA
00020  *
00021  *  http://sourceforge.net/projects/zbar
00022  *------------------------------------------------------------------------*/
00023 #ifndef _IMAGE_H_
00024 #define _IMAGE_H_
00025 
00026 #include <config.h>
00027 #ifdef HAVE_INTTYPES_H
00028 # include <inttypes.h>
00029 #endif
00030 #include <stdlib.h>
00031 #include <assert.h>
00032 
00033 #include <zbar.h>
00034 #include "error.h"
00035 #include "symbol.h"
00036 #include "refcnt.h"
00037 
00038 /* adapted from v4l2 spec */
00039 #define fourcc(a, b, c, d)                      \
00040     ((uint32_t)(a) | ((uint32_t)(b) << 8) |     \
00041      ((uint32_t)(c) << 16) | ((uint32_t)(d) << 24))
00042 
00043 /* unpack size/location of component */
00044 #define RGB_SIZE(c)   ((c) >> 5)
00045 #define RGB_OFFSET(c) ((c) & 0x1f)
00046 
00047 /* coarse image format categorization.
00048  * to limit conversion variations
00049  */
00050 typedef enum zbar_format_group_e {
00051     ZBAR_FMT_GRAY,
00052     ZBAR_FMT_YUV_PLANAR,
00053     ZBAR_FMT_YUV_PACKED,
00054     ZBAR_FMT_RGB_PACKED,
00055     ZBAR_FMT_YUV_NV,
00056     ZBAR_FMT_JPEG,
00057 
00058     /* enum size */
00059     ZBAR_FMT_NUM
00060 } zbar_format_group_t;
00061 
00062 
00063 struct zbar_image_s {
00064     uint32_t format;            /* fourcc image format code */
00065     unsigned width, height;     /* image size */
00066     const void *data;           /* image sample data */
00067     unsigned long datalen;      /* allocated/mapped size of data */
00068     void *userdata;             /* user specified data associated w/image */
00069 
00070     /* cleanup handler */
00071     zbar_image_cleanup_handler_t *cleanup;
00072     refcnt_t refcnt;            /* reference count */
00073     zbar_video_t *src;          /* originator */
00074     int srcidx;                 /* index used by originator */
00075     zbar_image_t *next;         /* internal image lists */
00076 
00077     unsigned seq;               /* page/frame sequence number */
00078     zbar_symbol_set_t *syms;    /* decoded result set */
00079 };
00080 
00081 /* description of an image format */
00082 typedef struct zbar_format_def_s {
00083     uint32_t format;                    /* fourcc */
00084     zbar_format_group_t group;          /* coarse categorization */
00085     union {
00086         uint8_t gen[4];                 /* raw bytes */
00087         struct {
00088             uint8_t bpp;                /* bits per pixel */
00089             uint8_t red, green, blue;   /* size/location a la RGB_BITS() */
00090         } rgb;
00091         struct {
00092             uint8_t xsub2, ysub2;       /* chroma subsampling in each axis */
00093             uint8_t packorder;          /* channel ordering flags
00094                                          *   bit0: 0=UV, 1=VU
00095                                          *   bit1: 0=Y/chroma, 1=chroma/Y
00096                                          */
00097         } yuv;
00098         uint32_t cmp;                   /* quick compare equivalent formats */
00099     } p;
00100 } zbar_format_def_t;
00101 
00102 
00103 extern int _zbar_best_format(uint32_t, uint32_t*, const uint32_t*);
00104 extern const zbar_format_def_t *_zbar_format_lookup(uint32_t);
00105 extern void _zbar_image_free(zbar_image_t*);
00106 
00107 #ifdef DEBUG_SVG
00108 extern int zbar_image_write_png(const zbar_image_t*, const char*);
00109 #else
00110 # define zbar_image_write_png(...)
00111 #endif
00112 
00113 static inline void _zbar_image_refcnt (zbar_image_t *img,
00114                                        int delta)
00115 {
00116     if(!_zbar_refcnt(&img->refcnt, delta) && delta <= 0) {
00117         if(img->cleanup)
00118             img->cleanup(img);
00119         if(!img->src)
00120             _zbar_image_free(img);
00121     }
00122 }
00123 
00124 static inline void _zbar_image_swap_symbols (zbar_image_t *a,
00125                                              zbar_image_t *b)
00126 {
00127     zbar_symbol_set_t *tmp = a->syms;
00128     a->syms = b->syms;
00129     b->syms = tmp;
00130 }
00131 
00132 #endif
00133