f365a06fb95a3597c4f426619375d729d9d9eb7a
[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 libavcodec documentation states that RGB555
34 * pixels shall be stored in native CPU endianness.
35 */
36
37 #include <stdint.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41
42 #include "libavutil/internal.h"
43 #include "avcodec.h"
44 #include "bytestream.h"
45 #include "internal.h"
46
47 typedef struct RpzaContext {
48
49 AVCodecContext *avctx;
50 AVFrame *frame;
51
52 GetByteContext gb;
53 } RpzaContext;
54
55 #define ADVANCE_BLOCK() \
56 { \
57 pixel_ptr += 4; \
58 if (pixel_ptr >= width) \
59 { \
60 pixel_ptr = 0; \
61 row_ptr += stride * 4; \
62 } \
63 total_blocks--; \
64 if (total_blocks < 0) \
65 { \
66 av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
67 return; \
68 } \
69 }
70
71 static void rpza_decode_stream(RpzaContext *s)
72 {
73 int width = s->avctx->width;
74 int stride = s->frame->linesize[0] / 2;
75 int row_inc = stride - 4;
76 int chunk_size;
77 uint16_t colorA = 0, colorB;
78 uint16_t color4[4];
79 uint16_t ta, tb;
80 uint16_t *pixels = (uint16_t *)s->frame->data[0];
81
82 int row_ptr = 0;
83 int pixel_ptr = 0;
84 int block_ptr;
85 int pixel_x, pixel_y;
86 int total_blocks;
87
88 /* First byte is always 0xe1. Warn if it's different */
89 if (bytestream2_peek_byte(&s->gb) != 0xe1)
90 av_log(s->avctx, AV_LOG_ERROR, "First chunk byte is 0x%02x instead of 0xe1\n",
91 bytestream2_peek_byte(&s->gb));
92
93 /* Get chunk size, ingnoring first byte */
94 chunk_size = bytestream2_get_be32(&s->gb) & 0x00FFFFFF;
95
96 /* If length mismatch use size from MOV file and try to decode anyway */
97 if (chunk_size != bytestream2_get_bytes_left(&s->gb) - 4)
98 av_log(s->avctx, AV_LOG_WARNING, "MOV chunk size != encoded chunk size\n");
99
100 /* Number of 4x4 blocks in frame. */
101 total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
102
103 /* Process chunk data */
104 while (bytestream2_get_bytes_left(&s->gb)) {
105 uint8_t opcode = bytestream2_get_byte(&s->gb); /* Get opcode */
106
107 int n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
108
109 /* If opcode MSbit is 0, we need more data to decide what to do */
110 if ((opcode & 0x80) == 0) {
111 colorA = (opcode << 8) | bytestream2_get_byte(&s->gb);
112 opcode = 0;
113 if ((bytestream2_peek_byte(&s->gb) & 0x80) != 0) {
114 /* Must behave as opcode 110xxxxx, using colorA computed
115 * above. Use fake opcode 0x20 to enter switch block at
116 * the right place */
117 opcode = 0x20;
118 n_blocks = 1;
119 }
120 }
121
122 n_blocks = FFMIN(n_blocks, total_blocks);
123
124 switch (opcode & 0xe0) {
125
126 /* Skip blocks */
127 case 0x80:
128 while (n_blocks--) {
129 ADVANCE_BLOCK();
130 }
131 break;
132
133 /* Fill blocks with one color */
134 case 0xa0:
135 colorA = bytestream2_get_be16(&s->gb);
136 while (n_blocks--) {
137 block_ptr = row_ptr + pixel_ptr;
138 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
139 for (pixel_x = 0; pixel_x < 4; pixel_x++){
140 pixels[block_ptr] = colorA;
141 block_ptr++;
142 }
143 block_ptr += row_inc;
144 }
145 ADVANCE_BLOCK();
146 }
147 break;
148
149 /* Fill blocks with 4 colors */
150 case 0xc0:
151 colorA = bytestream2_get_be16(&s->gb);
152 case 0x20:
153 colorB = bytestream2_get_be16(&s->gb);
154
155 /* sort out the colors */
156 color4[0] = colorB;
157 color4[1] = 0;
158 color4[2] = 0;
159 color4[3] = colorA;
160
161 /* red components */
162 ta = (colorA >> 10) & 0x1F;
163 tb = (colorB >> 10) & 0x1F;
164 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 10;
165 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 10;
166
167 /* green components */
168 ta = (colorA >> 5) & 0x1F;
169 tb = (colorB >> 5) & 0x1F;
170 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 5;
171 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 5;
172
173 /* blue components */
174 ta = colorA & 0x1F;
175 tb = colorB & 0x1F;
176 color4[1] |= ((11 * ta + 21 * tb) >> 5);
177 color4[2] |= ((21 * ta + 11 * tb) >> 5);
178
179 if (bytestream2_get_bytes_left(&s->gb) < n_blocks * 4)
180 return;
181 while (n_blocks--) {
182 block_ptr = row_ptr + pixel_ptr;
183 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
184 uint8_t index = bytestream2_get_byteu(&s->gb);
185 for (pixel_x = 0; pixel_x < 4; pixel_x++){
186 uint8_t idx = (index >> (2 * (3 - pixel_x))) & 0x03;
187 pixels[block_ptr] = color4[idx];
188 block_ptr++;
189 }
190 block_ptr += row_inc;
191 }
192 ADVANCE_BLOCK();
193 }
194 break;
195
196 /* Fill block with 16 colors */
197 case 0x00:
198 if (bytestream2_get_bytes_left(&s->gb) < 30)
199 return;
200 block_ptr = row_ptr + pixel_ptr;
201 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
202 for (pixel_x = 0; pixel_x < 4; pixel_x++){
203 /* We already have color of upper left pixel */
204 if ((pixel_y != 0) || (pixel_x != 0))
205 colorA = bytestream2_get_be16u(&s->gb);
206 pixels[block_ptr] = colorA;
207 block_ptr++;
208 }
209 block_ptr += row_inc;
210 }
211 ADVANCE_BLOCK();
212 break;
213
214 /* Unknown opcode */
215 default:
216 av_log(s->avctx, AV_LOG_ERROR, "Unknown opcode %d in rpza chunk."
217 " Skip remaining %d bytes of chunk data.\n", opcode,
218 bytestream2_get_bytes_left(&s->gb));
219 return;
220 } /* Opcode switch */
221 }
222 }
223
224 static av_cold int rpza_decode_init(AVCodecContext *avctx)
225 {
226 RpzaContext *s = avctx->priv_data;
227
228 s->avctx = avctx;
229 avctx->pix_fmt = AV_PIX_FMT_RGB555;
230
231 s->frame = av_frame_alloc();
232 if (!s->frame)
233 return AVERROR(ENOMEM);
234
235 return 0;
236 }
237
238 static int rpza_decode_frame(AVCodecContext *avctx,
239 void *data, int *got_frame,
240 AVPacket *avpkt)
241 {
242 RpzaContext *s = avctx->priv_data;
243 int ret;
244
245 bytestream2_init(&s->gb, avpkt->data, avpkt->size);
246
247 if ((ret = ff_reget_buffer(avctx, s->frame)) < 0) {
248 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
249 return ret;
250 }
251
252 rpza_decode_stream(s);
253
254 if ((ret = av_frame_ref(data, s->frame)) < 0)
255 return ret;
256
257 *got_frame = 1;
258
259 /* always report that the buffer was completely consumed */
260 return avpkt->size;
261 }
262
263 static av_cold int rpza_decode_end(AVCodecContext *avctx)
264 {
265 RpzaContext *s = avctx->priv_data;
266
267 av_frame_free(&s->frame);
268
269 return 0;
270 }
271
272 AVCodec ff_rpza_decoder = {
273 .name = "rpza",
274 .long_name = NULL_IF_CONFIG_SMALL("QuickTime video (RPZA)"),
275 .type = AVMEDIA_TYPE_VIDEO,
276 .id = AV_CODEC_ID_RPZA,
277 .priv_data_size = sizeof(RpzaContext),
278 .init = rpza_decode_init,
279 .close = rpza_decode_end,
280 .decode = rpza_decode_frame,
281 .capabilities = AV_CODEC_CAP_DR1,
282 };