Reindent after r24101.
[libav.git] / libavutil / pixdesc.h
1 /*
2 * pixel format descriptor
3 * Copyright (c) 2009 Michael Niedermayer <michaelni@gmx.at>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #ifndef AVUTIL_PIXDESC_H
23 #define AVUTIL_PIXDESC_H
24
25 #include <inttypes.h>
26
27 typedef struct AVComponentDescriptor{
28 uint16_t plane :2; ///< which of the 4 planes contains the component
29
30 /**
31 * Number of elements between 2 horizontally consecutive pixels minus 1.
32 * Elements are bits for bitstream formats, bytes otherwise.
33 */
34 uint16_t step_minus1 :3;
35
36 /**
37 * Number of elements before the component of the first pixel plus 1.
38 * Elements are bits for bitstream formats, bytes otherwise.
39 */
40 uint16_t offset_plus1 :3;
41 uint16_t shift :3; ///< number of least significant bits that must be shifted away to get the value
42 uint16_t depth_minus1 :4; ///< number of bits in the component minus 1
43 }AVComponentDescriptor;
44
45 /**
46 * Descriptor that unambiguously describes how the bits of a pixel are
47 * stored in the up to 4 data planes of an image. It also stores the
48 * subsampling factors and number of components.
49 *
50 * @note This is separate of the colorspace (RGB, YCbCr, YPbPr, JPEG-style YUV
51 * and all the YUV variants) AVPixFmtDescriptor just stores how values
52 * are stored not what these values represent.
53 */
54 typedef struct AVPixFmtDescriptor{
55 const char *name;
56 uint8_t nb_components; ///< The number of components each pixel has, (1-4)
57
58 /**
59 * Amount to shift the luma width right to find the chroma width.
60 * For YV12 this is 1 for example.
61 * chroma_width = -((-luma_width) >> log2_chroma_w)
62 * The note above is needed to ensure rounding up.
63 * This value only refers to the chroma components.
64 */
65 uint8_t log2_chroma_w; ///< chroma_width = -((-luma_width )>>log2_chroma_w)
66
67 /**
68 * Amount to shift the luma height right to find the chroma height.
69 * For YV12 this is 1 for example.
70 * chroma_height= -((-luma_height) >> log2_chroma_h)
71 * The note above is needed to ensure rounding up.
72 * This value only refers to the chroma components.
73 */
74 uint8_t log2_chroma_h;
75 uint8_t flags;
76
77 /**
78 * Parameters that describe how pixels are packed. If the format
79 * has chroma components, they must be stored in comp[1] and
80 * comp[2].
81 */
82 AVComponentDescriptor comp[4];
83 }AVPixFmtDescriptor;
84
85 #define PIX_FMT_BE 1 ///< Pixel format is big-endian.
86 #define PIX_FMT_PAL 2 ///< Pixel format has a palette in data[1], values are indexes in this palette.
87 #define PIX_FMT_BITSTREAM 4 ///< All values of a component are bit-wise packed end to end.
88 #define PIX_FMT_HWACCEL 8 ///< Pixel format is an HW accelerated format.
89
90 /**
91 * The array of all the pixel format descriptors.
92 */
93 extern const AVPixFmtDescriptor av_pix_fmt_descriptors[];
94
95 /**
96 * Read a line from an image, and write the values of the
97 * pixel format component c to dst.
98 *
99 * @param data the array containing the pointers to the planes of the image
100 * @param linesize the array containing the linesizes of the image
101 * @param desc the pixel format descriptor for the image
102 * @param x the horizontal coordinate of the first pixel to read
103 * @param y the vertical coordinate of the first pixel to read
104 * @param w the width of the line to read, that is the number of
105 * values to write to dst
106 * @param read_pal_component if not zero and the format is a paletted
107 * format writes the values corresponding to the palette
108 * component c in data[1] to dst, rather than the palette indexes in
109 * data[0]. The behavior is undefined if the format is not paletted.
110 */
111 void av_read_image_line(uint16_t *dst, const uint8_t *data[4], const int linesize[4],
112 const AVPixFmtDescriptor *desc, int x, int y, int c, int w, int read_pal_component);
113
114 /**
115 * Write the values from src to the pixel format component c of an
116 * image line.
117 *
118 * @param src array containing the values to write
119 * @param data the array containing the pointers to the planes of the
120 * image to write into. It is supposed to be zeroed.
121 * @param linesize the array containing the linesizes of the image
122 * @param desc the pixel format descriptor for the image
123 * @param x the horizontal coordinate of the first pixel to write
124 * @param y the vertical coordinate of the first pixel to write
125 * @param w the width of the line to write, that is the number of
126 * values to write to the image line
127 */
128 void av_write_image_line(const uint16_t *src, uint8_t *data[4], const int linesize[4],
129 const AVPixFmtDescriptor *desc, int x, int y, int c, int w);
130
131 /**
132 * Return the pixel format corresponding to name.
133 *
134 * If there is no pixel format with name name, then looks for a
135 * pixel format with the name corresponding to the native endian
136 * format of name.
137 * For example in a little-endian system, first looks for "gray16",
138 * then for "gray16le".
139 *
140 * Finally if no pixel format has been found, returns PIX_FMT_NONE.
141 */
142 enum PixelFormat av_get_pix_fmt(const char *name);
143
144 /**
145 * Return the number of bits per pixel used by the pixel format
146 * described by pixdesc.
147 *
148 * The returned number of bits refers to the number of bits actually
149 * used for storing the pixel information, that is padding bits are
150 * not counted.
151 */
152 int av_get_bits_per_pixel(const AVPixFmtDescriptor *pixdesc);
153
154 #endif /* AVUTIL_PIXDESC_H */