b7c09f95db774d1fbe2dc1682dd41ac00156b014
[libav.git] / libavcodec / rpza.c
1 /*
2 * Quicktime Video (RPZA) Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 */
20
21 /**
22 * @file rpza.c
23 * QT RPZA Video Decoder by Roberto Togni <rtogni@bresciaonline.it>
24 * For more information about the RPZA format, visit:
25 * http://www.pcisys.net/~melanson/codecs/
26 *
27 * The RPZA decoder outputs RGB555 colorspace data.
28 *
29 * Note that this decoder reads big endian RGB555 pixel values from the
30 * bytestream, arranges them in the host's endian order, and outputs
31 * them to the final rendered map in the same host endian order. This is
32 * intended behavior as the ffmpeg documentation states that RGB555 pixels
33 * shall be stored in native CPU endianness.
34 */
35
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40
41 #include "common.h"
42 #include "avcodec.h"
43 #include "dsputil.h"
44
45 typedef struct RpzaContext {
46
47 AVCodecContext *avctx;
48 DSPContext dsp;
49 AVFrame frame;
50
51 unsigned char *buf;
52 int size;
53
54 } RpzaContext;
55
56 #define BE_16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
57 #define BE_32(x) ((((uint8_t*)(x))[0] << 24) | \
58 (((uint8_t*)(x))[1] << 16) | \
59 (((uint8_t*)(x))[2] << 8) | \
60 ((uint8_t*)(x))[3])
61
62 #define ADVANCE_BLOCK() \
63 { \
64 pixel_ptr += 4; \
65 if (pixel_ptr >= width) \
66 { \
67 pixel_ptr = 0; \
68 row_ptr += stride * 4; \
69 } \
70 total_blocks--; \
71 if (total_blocks < 0) \
72 { \
73 av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
74 return; \
75 } \
76 }
77
78 static void rpza_decode_stream(RpzaContext *s)
79 {
80 int width = s->avctx->width;
81 int stride = s->frame.linesize[0] / 2;
82 int row_inc = stride - 4;
83 int stream_ptr = 0;
84 int chunk_size;
85 unsigned char opcode;
86 int n_blocks;
87 unsigned short colorA = 0, colorB;
88 unsigned short color4[4];
89 unsigned char index, idx;
90 unsigned short ta, tb;
91 unsigned short *pixels = (unsigned short *)s->frame.data[0];
92
93 int row_ptr = 0;
94 int pixel_ptr = 0;
95 int block_ptr;
96 int pixel_x, pixel_y;
97 int total_blocks;
98
99 /* First byte is always 0xe1. Warn if it's different */
100 if (s->buf[stream_ptr] != 0xe1)
101 av_log(s->avctx, AV_LOG_ERROR, "First chunk byte is 0x%02x instead of 0x1e\n",
102 s->buf[stream_ptr]);
103
104 /* Get chunk size, ingnoring first byte */
105 chunk_size = BE_32(&s->buf[stream_ptr]) & 0x00FFFFFF;
106 stream_ptr += 4;
107
108 /* If length mismatch use size from MOV file and try to decode anyway */
109 if (chunk_size != s->size)
110 av_log(s->avctx, AV_LOG_ERROR, "MOV chunk size != encoded chunk size; using MOV chunk size\n");
111
112 chunk_size = s->size;
113
114 /* Number of 4x4 blocks in frame. */
115 total_blocks = (s->avctx->width * s->avctx->height) / (4 * 4);
116
117 /* Process chunk data */
118 while (stream_ptr < chunk_size) {
119 opcode = s->buf[stream_ptr++]; /* Get opcode */
120
121 n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
122
123 /* If opcode MSbit is 0, we need more data to decide what to do */
124 if ((opcode & 0x80) == 0) {
125 colorA = (opcode << 8) | (s->buf[stream_ptr++]);
126 opcode = 0;
127 if ((s->buf[stream_ptr] & 0x80) != 0) {
128 /* Must behave as opcode 110xxxxx, using colorA computed
129 * above. Use fake opcode 0x20 to enter switch block at
130 * the right place */
131 opcode = 0x20;
132 n_blocks = 1;
133 }
134 }
135
136 switch (opcode & 0xe0) {
137
138 /* Skip blocks */
139 case 0x80:
140 while (n_blocks--) {
141 ADVANCE_BLOCK();
142 }
143 break;
144
145 /* Fill blocks with one color */
146 case 0xa0:
147 colorA = BE_16 (&s->buf[stream_ptr]);
148 stream_ptr += 2;
149 while (n_blocks--) {
150 block_ptr = row_ptr + pixel_ptr;
151 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
152 for (pixel_x = 0; pixel_x < 4; pixel_x++){
153 pixels[block_ptr] = colorA;
154 block_ptr++;
155 }
156 block_ptr += row_inc;
157 }
158 ADVANCE_BLOCK();
159 }
160 break;
161
162 /* Fill blocks with 4 colors */
163 case 0xc0:
164 colorA = BE_16 (&s->buf[stream_ptr]);
165 stream_ptr += 2;
166 case 0x20:
167 colorB = BE_16 (&s->buf[stream_ptr]);
168 stream_ptr += 2;
169
170 /* sort out the colors */
171 color4[0] = colorB;
172 color4[1] = 0;
173 color4[2] = 0;
174 color4[3] = colorA;
175
176 /* red components */
177 ta = (colorA >> 10) & 0x1F;
178 tb = (colorB >> 10) & 0x1F;
179 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 10;
180 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 10;
181
182 /* green components */
183 ta = (colorA >> 5) & 0x1F;
184 tb = (colorB >> 5) & 0x1F;
185 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 5;
186 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 5;
187
188 /* blue components */
189 ta = colorA & 0x1F;
190 tb = colorB & 0x1F;
191 color4[1] |= ((11 * ta + 21 * tb) >> 5);
192 color4[2] |= ((21 * ta + 11 * tb) >> 5);
193
194 while (n_blocks--) {
195 block_ptr = row_ptr + pixel_ptr;
196 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
197 index = s->buf[stream_ptr++];
198 for (pixel_x = 0; pixel_x < 4; pixel_x++){
199 idx = (index >> (2 * (3 - pixel_x))) & 0x03;
200 pixels[block_ptr] = color4[idx];
201 block_ptr++;
202 }
203 block_ptr += row_inc;
204 }
205 ADVANCE_BLOCK();
206 }
207 break;
208
209 /* Fill block with 16 colors */
210 case 0x00:
211 block_ptr = row_ptr + pixel_ptr;
212 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
213 for (pixel_x = 0; pixel_x < 4; pixel_x++){
214 /* We already have color of upper left pixel */
215 if ((pixel_y != 0) || (pixel_x !=0)) {
216 colorA = BE_16 (&s->buf[stream_ptr]);
217 stream_ptr += 2;
218 }
219 pixels[block_ptr] = colorA;
220 block_ptr++;
221 }
222 block_ptr += row_inc;
223 }
224 ADVANCE_BLOCK();
225 break;
226
227 /* Unknown opcode */
228 default:
229 av_log(s->avctx, AV_LOG_ERROR, "Unknown opcode %d in rpza chunk."
230 " Skip remaining %d bytes of chunk data.\n", opcode,
231 chunk_size - stream_ptr);
232 return;
233 } /* Opcode switch */
234 }
235 }
236
237 static int rpza_decode_init(AVCodecContext *avctx)
238 {
239 RpzaContext *s = (RpzaContext *)avctx->priv_data;
240
241 s->avctx = avctx;
242 avctx->pix_fmt = PIX_FMT_RGB555;
243 avctx->has_b_frames = 0;
244 dsputil_init(&s->dsp, avctx);
245
246 s->frame.data[0] = NULL;
247
248 return 0;
249 }
250
251 static int rpza_decode_frame(AVCodecContext *avctx,
252 void *data, int *data_size,
253 uint8_t *buf, int buf_size)
254 {
255 RpzaContext *s = (RpzaContext *)avctx->priv_data;
256
257 /* no supplementary picture */
258 if (buf_size == 0)
259 return 0;
260
261 s->buf = buf;
262 s->size = buf_size;
263
264 s->frame.reference = 1;
265 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
266 if (avctx->reget_buffer(avctx, &s->frame)) {
267 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
268 return -1;
269 }
270
271 rpza_decode_stream(s);
272
273 *data_size = sizeof(AVFrame);
274 *(AVFrame*)data = s->frame;
275
276 /* always report that the buffer was completely consumed */
277 return buf_size;
278 }
279
280 static int rpza_decode_end(AVCodecContext *avctx)
281 {
282 RpzaContext *s = (RpzaContext *)avctx->priv_data;
283
284 if (s->frame.data[0])
285 avctx->release_buffer(avctx, &s->frame);
286
287 return 0;
288 }
289
290 AVCodec rpza_decoder = {
291 "rpza",
292 CODEC_TYPE_VIDEO,
293 CODEC_ID_RPZA,
294 sizeof(RpzaContext),
295 rpza_decode_init,
296 NULL,
297 rpza_decode_end,
298 rpza_decode_frame,
299 CODEC_CAP_DR1,
300 };