lavc: fix decode_frame() third parameter semantics for video decoders
[libav.git] / libavcodec / 8bps.c
1 /*
2 * Quicktime Planar RGB (8BPS) Video Decoder
3 * Copyright (C) 2003 Roberto Togni
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 * QT 8BPS Video Decoder by Roberto Togni
25 * For more information about the 8BPS format, visit:
26 * http://www.pcisys.net/~melanson/codecs/
27 *
28 * Supports: PAL8 (RGB 8bpp, paletted)
29 * : BGR24 (RGB 24bpp) (can also output it as RGB32)
30 * : RGB32 (RGB 32bpp, 4th plane is probably alpha and it's ignored)
31 *
32 */
33
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37
38 #include "libavutil/internal.h"
39 #include "libavutil/intreadwrite.h"
40 #include "avcodec.h"
41 #include "internal.h"
42
43
44 static const enum AVPixelFormat pixfmt_rgb24[] = {
45 AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE };
46
47 /*
48 * Decoder context
49 */
50 typedef struct EightBpsContext {
51 AVCodecContext *avctx;
52 AVFrame pic;
53
54 unsigned char planes;
55 unsigned char planemap[4];
56
57 uint32_t pal[256];
58 } EightBpsContext;
59
60
61 /*
62 *
63 * Decode a frame
64 *
65 */
66 static int decode_frame(AVCodecContext *avctx, void *data,
67 int *got_frame, AVPacket *avpkt)
68 {
69 const uint8_t *buf = avpkt->data;
70 int buf_size = avpkt->size;
71 EightBpsContext * const c = avctx->priv_data;
72 const unsigned char *encoded = buf;
73 unsigned char *pixptr, *pixptr_end;
74 unsigned int height = avctx->height; // Real image height
75 unsigned int dlen, p, row;
76 const unsigned char *lp, *dp;
77 unsigned char count;
78 unsigned int px_inc;
79 unsigned int planes = c->planes;
80 unsigned char *planemap = c->planemap;
81
82 if (c->pic.data[0])
83 avctx->release_buffer(avctx, &c->pic);
84
85 c->pic.reference = 0;
86 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
87 if (ff_get_buffer(avctx, &c->pic) < 0){
88 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
89 return -1;
90 }
91
92 /* Set data pointer after line lengths */
93 dp = encoded + planes * (height << 1);
94
95 /* Ignore alpha plane, don't know what to do with it */
96 if (planes == 4)
97 planes--;
98
99 px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_RGB32);
100
101 for (p = 0; p < planes; p++) {
102 /* Lines length pointer for this plane */
103 lp = encoded + p * (height << 1);
104
105 /* Decode a plane */
106 for (row = 0; row < height; row++) {
107 pixptr = c->pic.data[0] + row * c->pic.linesize[0] + planemap[p];
108 pixptr_end = pixptr + c->pic.linesize[0];
109 dlen = av_be2ne16(*(const unsigned short *)(lp + row * 2));
110 /* Decode a row of this plane */
111 while (dlen > 0) {
112 if (dp + 1 >= buf + buf_size)
113 return -1;
114 if ((count = *dp++) <= 127) {
115 count++;
116 dlen -= count + 1;
117 if (pixptr + count * px_inc > pixptr_end)
118 break;
119 if (dp + count > buf + buf_size)
120 return -1;
121 while (count--) {
122 *pixptr = *dp++;
123 pixptr += px_inc;
124 }
125 } else {
126 count = 257 - count;
127 if (pixptr + count * px_inc > pixptr_end)
128 break;
129 while (count--) {
130 *pixptr = *dp;
131 pixptr += px_inc;
132 }
133 dp++;
134 dlen -= 2;
135 }
136 }
137 }
138 }
139
140 if (avctx->bits_per_coded_sample <= 8) {
141 const uint8_t *pal = av_packet_get_side_data(avpkt,
142 AV_PKT_DATA_PALETTE,
143 NULL);
144 if (pal) {
145 c->pic.palette_has_changed = 1;
146 memcpy(c->pal, pal, AVPALETTE_SIZE);
147 }
148
149 memcpy (c->pic.data[1], c->pal, AVPALETTE_SIZE);
150 }
151
152 *got_frame = 1;
153 *(AVFrame*)data = c->pic;
154
155 /* always report that the buffer was completely consumed */
156 return buf_size;
157 }
158
159
160 /*
161 *
162 * Init 8BPS decoder
163 *
164 */
165 static av_cold int decode_init(AVCodecContext *avctx)
166 {
167 EightBpsContext * const c = avctx->priv_data;
168
169 c->avctx = avctx;
170 c->pic.data[0] = NULL;
171
172 switch (avctx->bits_per_coded_sample) {
173 case 8:
174 avctx->pix_fmt = AV_PIX_FMT_PAL8;
175 c->planes = 1;
176 c->planemap[0] = 0; // 1st plane is palette indexes
177 break;
178 case 24:
179 avctx->pix_fmt = avctx->get_format(avctx, pixfmt_rgb24);
180 c->planes = 3;
181 c->planemap[0] = 2; // 1st plane is red
182 c->planemap[1] = 1; // 2nd plane is green
183 c->planemap[2] = 0; // 3rd plane is blue
184 break;
185 case 32:
186 avctx->pix_fmt = AV_PIX_FMT_RGB32;
187 c->planes = 4;
188 #if HAVE_BIGENDIAN
189 c->planemap[0] = 1; // 1st plane is red
190 c->planemap[1] = 2; // 2nd plane is green
191 c->planemap[2] = 3; // 3rd plane is blue
192 c->planemap[3] = 0; // 4th plane is alpha???
193 #else
194 c->planemap[0] = 2; // 1st plane is red
195 c->planemap[1] = 1; // 2nd plane is green
196 c->planemap[2] = 0; // 3rd plane is blue
197 c->planemap[3] = 3; // 4th plane is alpha???
198 #endif
199 break;
200 default:
201 av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
202 avctx->bits_per_coded_sample);
203 return -1;
204 }
205
206 return 0;
207 }
208
209
210
211
212 /*
213 *
214 * Uninit 8BPS decoder
215 *
216 */
217 static av_cold int decode_end(AVCodecContext *avctx)
218 {
219 EightBpsContext * const c = avctx->priv_data;
220
221 if (c->pic.data[0])
222 avctx->release_buffer(avctx, &c->pic);
223
224 return 0;
225 }
226
227
228
229 AVCodec ff_eightbps_decoder = {
230 .name = "8bps",
231 .type = AVMEDIA_TYPE_VIDEO,
232 .id = AV_CODEC_ID_8BPS,
233 .priv_data_size = sizeof(EightBpsContext),
234 .init = decode_init,
235 .close = decode_end,
236 .decode = decode_frame,
237 .capabilities = CODEC_CAP_DR1,
238 .long_name = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
239 };