]> mj.ucw.cz Git - libucw.git/blob - images/images.h
small bugfixes about transparency
[libucw.git] / images / images.h
1 #ifndef _IMAGES_IMAGES_H
2 #define _IMAGES_IMAGES_H
3
4 #include "lib/mempool.h"
5
6 /* image.c */
7
8 /* error handling */
9
10 enum image_error {
11   IMAGE_ERR_OK = 0,
12   IMAGE_ERR_UNSPECIFIED,
13   IMAGE_ERR_NOT_IMPLEMENTED,
14   IMAGE_ERR_INVALID_DIMENSIONS,
15   IMAGE_ERR_INVALID_FILE_FORMAT,
16   IMAGE_ERR_INVALID_PIXEL_FORMAT,
17   IMAGE_ERR_READ_FAILED,
18   IMAGE_ERR_WRITE_FAILED,
19   IMAGE_ERR_MAX
20 };
21
22 struct image_thread {
23   byte *err_msg;
24   enum image_error err_code;
25   struct mempool *pool;
26 };
27
28 void image_thread_init(struct image_thread *thread);
29 void image_thread_cleanup(struct image_thread *thread);
30
31 static inline void
32 image_thread_flush(struct image_thread *thread)
33 {
34   thread->err_code = 0;
35   thread->err_msg = NULL;
36   mp_flush(thread->pool);
37 }
38
39 static inline void
40 image_thread_err(struct image_thread *thread, uns code, char *msg)
41 {
42   thread->err_code = code;
43   thread->err_msg = (byte *)msg;
44 }
45
46 static inline void
47 image_thread_err_dup(struct image_thread *thread, uns code, char *msg)
48 {
49   thread->err_code = code;
50   thread->err_msg = mp_strdup(thread->pool, msg);
51 }
52
53 void image_thread_err_format(struct image_thread *thread, uns code, char *msg, ...);
54
55 /* basic image manupulation */
56
57 #define IMAGE_MAX_SIZE          0xffffU /* maximum number of cols/rows, must be <(1<<16) */
58 #define IMAGE_SSE_ALIGN_SIZE    (MAX(16, sizeof(uns)))
59
60 enum color_space {
61   COLOR_SPACE_UNKNOWN,
62   COLOR_SPACE_GRAYSCALE,
63   COLOR_SPACE_RGB,
64   COLOR_SPACE_MAX
65 };
66
67 enum image_flag {
68   IMAGE_COLOR_SPACE = 0x7,      /* mask for enum color_space */
69   IMAGE_ALPHA = 0x8,            /* alpha channel */
70   IMAGE_PIXELS_ALIGNED = 0x10,  /* align pixel size to the nearest power of two  */
71   IMAGE_SSE_ALIGNED = 0x20,     /* align scanlines to multiples of 16 bytes (both start and size) */
72   IMAGE_CHANNELS_FORMAT = IMAGE_COLOR_SPACE | IMAGE_ALPHA,
73   IMAGE_PIXEL_FORMAT = IMAGE_CHANNELS_FORMAT | IMAGE_PIXELS_ALIGNED,
74   IMAGE_ALIGNED = IMAGE_PIXELS_ALIGNED | IMAGE_SSE_ALIGNED,
75 };
76
77 struct image {
78   byte *pixels;                 /* left top pixel, there are at least sizeof(uns)
79                                    unsed bytes after the buffer (possible optimizations) */
80   u32 cols;                     /* number of columns */
81   u32 rows;                     /* number of rows */
82   u32 pixel_size;               /* size of pixel (1, 2, 3 or 4) */
83   u32 row_size;                 /* scanline size in bytes */
84   u32 image_size;               /* size of pixels buffer (rows * rows_size) */
85   u32 flags;                    /* enum image_flag */
86 };
87
88 struct image *image_new(struct image_thread *it, uns cols, uns rows, uns flags, struct mempool *pool);
89 struct image *image_clone(struct image_thread *it, struct image *src, uns flags, struct mempool *pool);
90 void image_destroy(struct image *img); /* only with NULL mempool */
91 void image_clear(struct image_thread *it, struct image *img);
92
93 byte *color_space_to_name(enum color_space cs);
94 byte *image_channels_format_to_name(uns format);
95 uns image_name_to_channels_format(byte *name);
96
97 struct color {
98   byte c[3];
99   byte color_space;
100 } PACKED;
101
102 /* scale.c */
103
104 int image_scale(struct image_thread *thread, struct image *dest, struct image *src);
105 void image_dimensions_fit_to_box(u32 *cols, u32 *rows, u32 max_cols, u32 max_rows, uns upsample);
106
107 /* alpha.c */
108
109 int image_apply_background(struct image_thread *thread, struct image *dest, struct image *src, struct color *background);
110
111 /* image-io.c */
112
113 enum image_format {
114   IMAGE_FORMAT_UNDEFINED,
115   IMAGE_FORMAT_JPEG,
116   IMAGE_FORMAT_PNG,
117   IMAGE_FORMAT_GIF,
118   IMAGE_FORMAT_MAX
119 };
120
121 struct image_io {
122                                         /*  R - read_header input */
123                                         /*   H - read_header output */
124                                         /*    I - read_data input */
125                                         /*     O - read_data output */
126                                         /*      W - write input */
127
128   struct image *image;                  /* [   OW] - image data */
129   enum image_format format;             /* [R   W] - file format (IMAGE_FORMAT_x) */
130   struct fastbuf *fastbuf;              /* [R   W] - source/destination stream */
131   struct mempool *pool;                 /* [  I  ] - parameter to image_new */
132   u32 cols;                             /* [ HI  ] - number of columns, parameter to image_new */
133   u32 rows;                             /* [ HI  ] - number of rows, parameter to image_new */
134   u32 flags;                            /* [ HI  ] - see enum image_io_flags */
135   u32 jpeg_quality;                     /* [    W] - JPEG compression quality (1..100) */
136   u32 number_of_colors;                 /* [ H   ] - number of image colors */
137   struct color background_color;        /* [ HI  ] - background color, zero if undefined */
138
139   /* internals */
140   struct image_thread *thread;
141   struct mempool *internal_pool;
142   int image_destroy;
143   void *read_data;
144   void (*read_cancel)(struct image_io *io);
145 };
146
147 enum image_io_flags {
148   IMAGE_IO_IMAGE_FLAGS = 0xffff,        /* [ HI  ] - mask of parameters to image new, read_header fills IMAGE_CHANNELS_FORMAT */
149   IMAGE_IO_HAS_PALETTE = 0x10000,       /* [ H   ] - true for image with indexed colors */
150   IMAGE_IO_USE_BACKGROUND = 0x20000,    /* [  I  ] - merge transparent pixels with background_color */
151 };
152
153 void image_io_init(struct image_thread *it, struct image_io *io);
154 void image_io_cleanup(struct image_io *io);
155 void image_io_reset(struct image_io *io);
156
157 int image_io_read_header(struct image_io *io);
158 struct image *image_io_read_data(struct image_io *io, int ref);
159 struct image *image_io_read(struct image_io *io, int ref);
160
161 int image_io_write(struct image_io *io);
162
163 byte *image_format_to_extension(enum image_format format);
164 enum image_format image_extension_to_format(byte *extension);
165 enum image_format image_file_name_to_format(byte *file_name);
166
167 #endif