53e7df810a49dcb41fde273ea7fb637014f0a3cd
[libav.git] / libavcodec / imgconvert.c
1 /*
2 * Misc image conversion routines
3 * Copyright (c) 2001, 2002, 2003 Fabrice Bellard
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * misc image conversion routines
25 */
26
27 /* TODO:
28 * - write 'ffimg' program to test all the image related stuff
29 * - move all api to slice based system
30 * - integrate deinterlacing, postprocessing and scaling in the conversion process
31 */
32
33 #include "avcodec.h"
34 #include "imgconvert.h"
35 #include "internal.h"
36 #include "mathops.h"
37 #include "libavutil/colorspace.h"
38 #include "libavutil/common.h"
39 #include "libavutil/pixdesc.h"
40 #include "libavutil/imgutils.h"
41
42 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift)
43 {
44 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
45 *h_shift = desc->log2_chroma_w;
46 *v_shift = desc->log2_chroma_h;
47 }
48
49 static int is_gray(const AVPixFmtDescriptor *desc)
50 {
51 return desc->nb_components - (desc->flags & AV_PIX_FMT_FLAG_ALPHA) == 1;
52 }
53
54 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt,
55 enum AVPixelFormat src_pix_fmt,
56 int has_alpha)
57 {
58 const AVPixFmtDescriptor *src_desc = av_pix_fmt_desc_get(src_pix_fmt);
59 const AVPixFmtDescriptor *dst_desc = av_pix_fmt_desc_get(dst_pix_fmt);
60 int loss, i, nb_components = FFMIN(src_desc->nb_components,
61 dst_desc->nb_components);
62
63 /* compute loss */
64 loss = 0;
65
66 if (dst_pix_fmt == src_pix_fmt)
67 return 0;
68
69 for (i = 0; i < nb_components; i++)
70 if (src_desc->comp[i].depth > dst_desc->comp[i].depth)
71 loss |= FF_LOSS_DEPTH;
72
73 if (dst_desc->log2_chroma_w > src_desc->log2_chroma_w ||
74 dst_desc->log2_chroma_h > src_desc->log2_chroma_h)
75 loss |= FF_LOSS_RESOLUTION;
76
77 if ((src_desc->flags & AV_PIX_FMT_FLAG_RGB) != (dst_desc->flags & AV_PIX_FMT_FLAG_RGB))
78 loss |= FF_LOSS_COLORSPACE;
79
80 if (has_alpha && !(dst_desc->flags & AV_PIX_FMT_FLAG_ALPHA) &&
81 (src_desc->flags & AV_PIX_FMT_FLAG_ALPHA))
82 loss |= FF_LOSS_ALPHA;
83
84 if (dst_pix_fmt == AV_PIX_FMT_PAL8 && !is_gray(src_desc))
85 return loss | FF_LOSS_COLORQUANT;
86
87 if (src_desc->nb_components > dst_desc->nb_components)
88 if (is_gray(dst_desc))
89 loss |= FF_LOSS_CHROMA;
90
91 return loss;
92 }
93
94 static enum AVPixelFormat avcodec_find_best_pix_fmt1(enum AVPixelFormat *pix_fmt_list,
95 enum AVPixelFormat src_pix_fmt,
96 int has_alpha,
97 int loss_mask)
98 {
99 int dist, i, loss, min_dist;
100 enum AVPixelFormat dst_pix_fmt;
101
102 /* find exact color match with smallest size */
103 dst_pix_fmt = AV_PIX_FMT_NONE;
104 min_dist = 0x7fffffff;
105 i = 0;
106 while (pix_fmt_list[i] != AV_PIX_FMT_NONE) {
107 enum AVPixelFormat pix_fmt = pix_fmt_list[i];
108
109 if (i > AV_PIX_FMT_NB) {
110 av_log(NULL, AV_LOG_ERROR, "Pixel format list longer than expected, "
111 "it is either not properly terminated or contains duplicates\n");
112 return AV_PIX_FMT_NONE;
113 }
114
115 loss = avcodec_get_pix_fmt_loss(pix_fmt, src_pix_fmt, has_alpha) & loss_mask;
116 if (loss == 0) {
117 dist = av_get_bits_per_pixel(av_pix_fmt_desc_get(pix_fmt));
118 if (dist < min_dist) {
119 min_dist = dist;
120 dst_pix_fmt = pix_fmt;
121 }
122 }
123 i++;
124 }
125 return dst_pix_fmt;
126 }
127
128 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat *pix_fmt_list,
129 enum AVPixelFormat src_pix_fmt,
130 int has_alpha, int *loss_ptr)
131 {
132 enum AVPixelFormat dst_pix_fmt;
133 int loss_mask, i;
134 static const int loss_mask_order[] = {
135 ~0, /* no loss first */
136 ~FF_LOSS_ALPHA,
137 ~FF_LOSS_RESOLUTION,
138 ~(FF_LOSS_COLORSPACE | FF_LOSS_RESOLUTION),
139 ~FF_LOSS_COLORQUANT,
140 ~FF_LOSS_DEPTH,
141 0,
142 };
143
144 /* try with successive loss */
145 i = 0;
146 for(;;) {
147 loss_mask = loss_mask_order[i++];
148 dst_pix_fmt = avcodec_find_best_pix_fmt1(pix_fmt_list, src_pix_fmt,
149 has_alpha, loss_mask);
150 if (dst_pix_fmt >= 0)
151 goto found;
152 if (loss_mask == 0)
153 break;
154 }
155 return AV_PIX_FMT_NONE;
156 found:
157 if (loss_ptr)
158 *loss_ptr = avcodec_get_pix_fmt_loss(dst_pix_fmt, src_pix_fmt, has_alpha);
159 return dst_pix_fmt;
160 }
161
162 /* 2x2 -> 1x1 */
163 void ff_shrink22(uint8_t *dst, int dst_wrap,
164 const uint8_t *src, int src_wrap,
165 int width, int height)
166 {
167 int w;
168 const uint8_t *s1, *s2;
169 uint8_t *d;
170
171 for(;height > 0; height--) {
172 s1 = src;
173 s2 = s1 + src_wrap;
174 d = dst;
175 for(w = width;w >= 4; w-=4) {
176 d[0] = (s1[0] + s1[1] + s2[0] + s2[1] + 2) >> 2;
177 d[1] = (s1[2] + s1[3] + s2[2] + s2[3] + 2) >> 2;
178 d[2] = (s1[4] + s1[5] + s2[4] + s2[5] + 2) >> 2;
179 d[3] = (s1[6] + s1[7] + s2[6] + s2[7] + 2) >> 2;
180 s1 += 8;
181 s2 += 8;
182 d += 4;
183 }
184 for(;w > 0; w--) {
185 d[0] = (s1[0] + s1[1] + s2[0] + s2[1] + 2) >> 2;
186 s1 += 2;
187 s2 += 2;
188 d++;
189 }
190 src += 2 * src_wrap;
191 dst += dst_wrap;
192 }
193 }
194
195 /* 4x4 -> 1x1 */
196 void ff_shrink44(uint8_t *dst, int dst_wrap,
197 const uint8_t *src, int src_wrap,
198 int width, int height)
199 {
200 int w;
201 const uint8_t *s1, *s2, *s3, *s4;
202 uint8_t *d;
203
204 for(;height > 0; height--) {
205 s1 = src;
206 s2 = s1 + src_wrap;
207 s3 = s2 + src_wrap;
208 s4 = s3 + src_wrap;
209 d = dst;
210 for(w = width;w > 0; w--) {
211 d[0] = (s1[0] + s1[1] + s1[2] + s1[3] +
212 s2[0] + s2[1] + s2[2] + s2[3] +
213 s3[0] + s3[1] + s3[2] + s3[3] +
214 s4[0] + s4[1] + s4[2] + s4[3] + 8) >> 4;
215 s1 += 4;
216 s2 += 4;
217 s3 += 4;
218 s4 += 4;
219 d++;
220 }
221 src += 4 * src_wrap;
222 dst += dst_wrap;
223 }
224 }
225
226 /* 8x8 -> 1x1 */
227 void ff_shrink88(uint8_t *dst, int dst_wrap,
228 const uint8_t *src, int src_wrap,
229 int width, int height)
230 {
231 int w, i;
232
233 for(;height > 0; height--) {
234 for(w = width;w > 0; w--) {
235 int tmp=0;
236 for(i=0; i<8; i++){
237 tmp += src[0] + src[1] + src[2] + src[3] + src[4] + src[5] + src[6] + src[7];
238 src += src_wrap;
239 }
240 *(dst++) = (tmp + 32)>>6;
241 src += 8 - 8*src_wrap;
242 }
243 src += 8*src_wrap - 8*width;
244 dst += dst_wrap - width;
245 }
246 }
247
248 /* return true if yuv planar */
249 static inline int is_yuv_planar(const AVPixFmtDescriptor *desc)
250 {
251 return (!(desc->flags & AV_PIX_FMT_FLAG_RGB) &&
252 (desc->flags & AV_PIX_FMT_FLAG_PLANAR));
253 }
254
255 int av_picture_crop(AVPicture *dst, const AVPicture *src,
256 enum AVPixelFormat pix_fmt, int top_band, int left_band)
257 {
258 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
259 int y_shift;
260 int x_shift;
261
262 if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB || !is_yuv_planar(desc))
263 return -1;
264
265 y_shift = desc->log2_chroma_h;
266 x_shift = desc->log2_chroma_w;
267
268 dst->data[0] = src->data[0] + (top_band * src->linesize[0]) + left_band;
269 dst->data[1] = src->data[1] + ((top_band >> y_shift) * src->linesize[1]) + (left_band >> x_shift);
270 dst->data[2] = src->data[2] + ((top_band >> y_shift) * src->linesize[2]) + (left_band >> x_shift);
271
272 dst->linesize[0] = src->linesize[0];
273 dst->linesize[1] = src->linesize[1];
274 dst->linesize[2] = src->linesize[2];
275 return 0;
276 }
277
278 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width,
279 enum AVPixelFormat pix_fmt, int padtop, int padbottom, int padleft, int padright,
280 int *color)
281 {
282 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
283 uint8_t *optr;
284 int y_shift;
285 int x_shift;
286 int yheight;
287 int i, y;
288
289 if (pix_fmt < 0 || pix_fmt >= AV_PIX_FMT_NB ||
290 !is_yuv_planar(desc)) return -1;
291
292 for (i = 0; i < 3; i++) {
293 x_shift = i ? desc->log2_chroma_w : 0;
294 y_shift = i ? desc->log2_chroma_h : 0;
295
296 if (padtop || padleft) {
297 memset(dst->data[i], color[i],
298 dst->linesize[i] * (padtop >> y_shift) + (padleft >> x_shift));
299 }
300
301 if (padleft || padright) {
302 optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
303 (dst->linesize[i] - (padright >> x_shift));
304 yheight = (height - 1 - (padtop + padbottom)) >> y_shift;
305 for (y = 0; y < yheight; y++) {
306 memset(optr, color[i], (padleft + padright) >> x_shift);
307 optr += dst->linesize[i];
308 }
309 }
310
311 if (src) { /* first line */
312 uint8_t *iptr = src->data[i];
313 optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
314 (padleft >> x_shift);
315 memcpy(optr, iptr, (width - padleft - padright) >> x_shift);
316 iptr += src->linesize[i];
317 optr = dst->data[i] + dst->linesize[i] * (padtop >> y_shift) +
318 (dst->linesize[i] - (padright >> x_shift));
319 yheight = (height - 1 - (padtop + padbottom)) >> y_shift;
320 for (y = 0; y < yheight; y++) {
321 memset(optr, color[i], (padleft + padright) >> x_shift);
322 memcpy(optr + ((padleft + padright) >> x_shift), iptr,
323 (width - padleft - padright) >> x_shift);
324 iptr += src->linesize[i];
325 optr += dst->linesize[i];
326 }
327 }
328
329 if (padbottom || padright) {
330 optr = dst->data[i] + dst->linesize[i] *
331 ((height - padbottom) >> y_shift) - (padright >> x_shift);
332 memset(optr, color[i],dst->linesize[i] *
333 (padbottom >> y_shift) + (padright >> x_shift));
334 }
335 }
336 return 0;
337 }