3fb3dc5b9512a9ab92ff71e89e56e6a5e900932d
[libav.git] / libavcodec / rpza.c
1 /*
2 * Quicktime Video (RPZA) Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
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 RPZA Video Decoder by Roberto Togni
25 * For more information about the RPZA format, visit:
26 * http://www.pcisys.net/~melanson/codecs/
27 *
28 * The RPZA decoder outputs RGB555 colorspace data.
29 *
30 * Note that this decoder reads big endian RGB555 pixel values from the
31 * bytestream, arranges them in the host's endian order, and outputs
32 * them to the final rendered map in the same host endian order. This is
33 * intended behavior as the ffmpeg documentation states that RGB555 pixels
34 * shall be stored in native CPU endianness.
35 */
36
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40
41 #include "libavutil/intreadwrite.h"
42 #include "avcodec.h"
43
44 typedef struct RpzaContext {
45
46 AVCodecContext *avctx;
47 AVFrame frame;
48
49 const unsigned char *buf;
50 int size;
51
52 } RpzaContext;
53
54 #define ADVANCE_BLOCK() \
55 { \
56 pixel_ptr += 4; \
57 if (pixel_ptr >= width) \
58 { \
59 pixel_ptr = 0; \
60 row_ptr += stride * 4; \
61 } \
62 total_blocks--; \
63 if (total_blocks < 0) \
64 { \
65 av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
66 return; \
67 } \
68 }
69
70 static void rpza_decode_stream(RpzaContext *s)
71 {
72 int width = s->avctx->width;
73 int stride = s->frame.linesize[0] / 2;
74 int row_inc = stride - 4;
75 int stream_ptr = 0;
76 int chunk_size;
77 unsigned char opcode;
78 int n_blocks;
79 unsigned short colorA = 0, colorB;
80 unsigned short color4[4];
81 unsigned char index, idx;
82 unsigned short ta, tb;
83 unsigned short *pixels = (unsigned short *)s->frame.data[0];
84
85 int row_ptr = 0;
86 int pixel_ptr = 0;
87 int block_ptr;
88 int pixel_x, pixel_y;
89 int total_blocks;
90
91 /* First byte is always 0xe1. Warn if it's different */
92 if (s->buf[stream_ptr] != 0xe1)
93 av_log(s->avctx, AV_LOG_ERROR, "First chunk byte is 0x%02x instead of 0xe1\n",
94 s->buf[stream_ptr]);
95
96 /* Get chunk size, ingnoring first byte */
97 chunk_size = AV_RB32(&s->buf[stream_ptr]) & 0x00FFFFFF;
98 stream_ptr += 4;
99
100 /* If length mismatch use size from MOV file and try to decode anyway */
101 if (chunk_size != s->size)
102 av_log(s->avctx, AV_LOG_ERROR, "MOV chunk size != encoded chunk size; using MOV chunk size\n");
103
104 chunk_size = s->size;
105
106 /* Number of 4x4 blocks in frame. */
107 total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
108
109 /* Process chunk data */
110 while (stream_ptr < chunk_size) {
111 opcode = s->buf[stream_ptr++]; /* Get opcode */
112
113 n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
114
115 /* If opcode MSbit is 0, we need more data to decide what to do */
116 if ((opcode & 0x80) == 0) {
117 colorA = (opcode << 8) | (s->buf[stream_ptr++]);
118 opcode = 0;
119 if ((s->buf[stream_ptr] & 0x80) != 0) {
120 /* Must behave as opcode 110xxxxx, using colorA computed
121 * above. Use fake opcode 0x20 to enter switch block at
122 * the right place */
123 opcode = 0x20;
124 n_blocks = 1;
125 }
126 }
127
128 switch (opcode & 0xe0) {
129
130 /* Skip blocks */
131 case 0x80:
132 while (n_blocks--) {
133 ADVANCE_BLOCK();
134 }
135 break;
136
137 /* Fill blocks with one color */
138 case 0xa0:
139 colorA = AV_RB16 (&s->buf[stream_ptr]);
140 stream_ptr += 2;
141 while (n_blocks--) {
142 block_ptr = row_ptr + pixel_ptr;
143 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
144 for (pixel_x = 0; pixel_x < 4; pixel_x++){
145 pixels[block_ptr] = colorA;
146 block_ptr++;
147 }
148 block_ptr += row_inc;
149 }
150 ADVANCE_BLOCK();
151 }
152 break;
153
154 /* Fill blocks with 4 colors */
155 case 0xc0:
156 colorA = AV_RB16 (&s->buf[stream_ptr]);
157 stream_ptr += 2;
158 case 0x20:
159 colorB = AV_RB16 (&s->buf[stream_ptr]);
160 stream_ptr += 2;
161
162 /* sort out the colors */
163 color4[0] = colorB;
164 color4[1] = 0;
165 color4[2] = 0;
166 color4[3] = colorA;
167
168 /* red components */
169 ta = (colorA >> 10) & 0x1F;
170 tb = (colorB >> 10) & 0x1F;
171 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 10;
172 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 10;
173
174 /* green components */
175 ta = (colorA >> 5) & 0x1F;
176 tb = (colorB >> 5) & 0x1F;
177 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 5;
178 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 5;
179
180 /* blue components */
181 ta = colorA & 0x1F;
182 tb = colorB & 0x1F;
183 color4[1] |= ((11 * ta + 21 * tb) >> 5);
184 color4[2] |= ((21 * ta + 11 * tb) >> 5);
185
186 while (n_blocks--) {
187 block_ptr = row_ptr + pixel_ptr;
188 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
189 index = s->buf[stream_ptr++];
190 for (pixel_x = 0; pixel_x < 4; pixel_x++){
191 idx = (index >> (2 * (3 - pixel_x))) & 0x03;
192 pixels[block_ptr] = color4[idx];
193 block_ptr++;
194 }
195 block_ptr += row_inc;
196 }
197 ADVANCE_BLOCK();
198 }
199 break;
200
201 /* Fill block with 16 colors */
202 case 0x00:
203 block_ptr = row_ptr + pixel_ptr;
204 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
205 for (pixel_x = 0; pixel_x < 4; pixel_x++){
206 /* We already have color of upper left pixel */
207 if ((pixel_y != 0) || (pixel_x !=0)) {
208 colorA = AV_RB16 (&s->buf[stream_ptr]);
209 stream_ptr += 2;
210 }
211 pixels[block_ptr] = colorA;
212 block_ptr++;
213 }
214 block_ptr += row_inc;
215 }
216 ADVANCE_BLOCK();
217 break;
218
219 /* Unknown opcode */
220 default:
221 av_log(s->avctx, AV_LOG_ERROR, "Unknown opcode %d in rpza chunk."
222 " Skip remaining %d bytes of chunk data.\n", opcode,
223 chunk_size - stream_ptr);
224 return;
225 } /* Opcode switch */
226 }
227 }
228
229 static av_cold int rpza_decode_init(AVCodecContext *avctx)
230 {
231 RpzaContext *s = avctx->priv_data;
232
233 s->avctx = avctx;
234 avctx->pix_fmt = PIX_FMT_RGB555;
235
236 s->frame.data[0] = NULL;
237
238 return 0;
239 }
240
241 static int rpza_decode_frame(AVCodecContext *avctx,
242 void *data, int *data_size,
243 AVPacket *avpkt)
244 {
245 const uint8_t *buf = avpkt->data;
246 int buf_size = avpkt->size;
247 RpzaContext *s = avctx->priv_data;
248
249 s->buf = buf;
250 s->size = buf_size;
251
252 s->frame.reference = 1;
253 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
254 if (avctx->reget_buffer(avctx, &s->frame)) {
255 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
256 return -1;
257 }
258
259 rpza_decode_stream(s);
260
261 *data_size = sizeof(AVFrame);
262 *(AVFrame*)data = s->frame;
263
264 /* always report that the buffer was completely consumed */
265 return buf_size;
266 }
267
268 static av_cold int rpza_decode_end(AVCodecContext *avctx)
269 {
270 RpzaContext *s = avctx->priv_data;
271
272 if (s->frame.data[0])
273 avctx->release_buffer(avctx, &s->frame);
274
275 return 0;
276 }
277
278 AVCodec ff_rpza_decoder = {
279 .name = "rpza",
280 .type = AVMEDIA_TYPE_VIDEO,
281 .id = CODEC_ID_RPZA,
282 .priv_data_size = sizeof(RpzaContext),
283 .init = rpza_decode_init,
284 .close = rpza_decode_end,
285 .decode = rpza_decode_frame,
286 .capabilities = CODEC_CAP_DR1,
287 .long_name = NULL_IF_CONFIG_SMALL("QuickTime video (RPZA)"),
288 };