rpza: Check the blocks left before processing one
[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 CHECK_BLOCK() \
56 if (total_blocks < 1) { \
57 av_log(s->avctx, AV_LOG_ERROR, \
58 "Block counter just went negative (this should not happen)\n"); \
59 return AVERROR_INVALIDDATA; \
60 } \
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 }
72
73 static int rpza_decode_stream(RpzaContext *s)
74 {
75 int width = s->avctx->width;
76 int stride = s->frame->linesize[0] / 2;
77 int row_inc = stride - 4;
78 int chunk_size;
79 uint16_t colorA = 0, colorB;
80 uint16_t color4[4];
81 uint16_t ta, tb;
82 uint16_t *pixels = (uint16_t *)s->frame->data[0];
83
84 int row_ptr = 0;
85 int pixel_ptr = 0;
86 int block_ptr;
87 int pixel_x, pixel_y;
88 int total_blocks;
89
90 /* First byte is always 0xe1. Warn if it's different */
91 if (bytestream2_peek_byte(&s->gb) != 0xe1)
92 av_log(s->avctx, AV_LOG_ERROR, "First chunk byte is 0x%02x instead of 0xe1\n",
93 bytestream2_peek_byte(&s->gb));
94
95 /* Get chunk size, ingnoring first byte */
96 chunk_size = bytestream2_get_be32(&s->gb) & 0x00FFFFFF;
97
98 /* If length mismatch use size from MOV file and try to decode anyway */
99 if (chunk_size != bytestream2_get_bytes_left(&s->gb) - 4)
100 av_log(s->avctx, AV_LOG_WARNING, "MOV chunk size != encoded chunk size\n");
101
102 /* Number of 4x4 blocks in frame. */
103 total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
104
105 /* Process chunk data */
106 while (bytestream2_get_bytes_left(&s->gb)) {
107 uint8_t opcode = bytestream2_get_byte(&s->gb); /* Get opcode */
108
109 int n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
110
111 /* If opcode MSbit is 0, we need more data to decide what to do */
112 if ((opcode & 0x80) == 0) {
113 colorA = (opcode << 8) | bytestream2_get_byte(&s->gb);
114 opcode = 0;
115 if ((bytestream2_peek_byte(&s->gb) & 0x80) != 0) {
116 /* Must behave as opcode 110xxxxx, using colorA computed
117 * above. Use fake opcode 0x20 to enter switch block at
118 * the right place */
119 opcode = 0x20;
120 n_blocks = 1;
121 }
122 }
123
124 n_blocks = FFMIN(n_blocks, total_blocks);
125
126 switch (opcode & 0xe0) {
127
128 /* Skip blocks */
129 case 0x80:
130 while (n_blocks--) {
131 CHECK_BLOCK();
132 ADVANCE_BLOCK();
133 }
134 break;
135
136 /* Fill blocks with one color */
137 case 0xa0:
138 colorA = bytestream2_get_be16(&s->gb);
139 while (n_blocks--) {
140 CHECK_BLOCK();
141 block_ptr = row_ptr + pixel_ptr;
142 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
143 for (pixel_x = 0; pixel_x < 4; pixel_x++){
144 pixels[block_ptr] = colorA;
145 block_ptr++;
146 }
147 block_ptr += row_inc;
148 }
149 ADVANCE_BLOCK();
150 }
151 break;
152
153 /* Fill blocks with 4 colors */
154 case 0xc0:
155 colorA = bytestream2_get_be16(&s->gb);
156 case 0x20:
157 colorB = bytestream2_get_be16(&s->gb);
158
159 /* sort out the colors */
160 color4[0] = colorB;
161 color4[1] = 0;
162 color4[2] = 0;
163 color4[3] = colorA;
164
165 /* red components */
166 ta = (colorA >> 10) & 0x1F;
167 tb = (colorB >> 10) & 0x1F;
168 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 10;
169 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 10;
170
171 /* green components */
172 ta = (colorA >> 5) & 0x1F;
173 tb = (colorB >> 5) & 0x1F;
174 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 5;
175 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 5;
176
177 /* blue components */
178 ta = colorA & 0x1F;
179 tb = colorB & 0x1F;
180 color4[1] |= ((11 * ta + 21 * tb) >> 5);
181 color4[2] |= ((21 * ta + 11 * tb) >> 5);
182
183 if (bytestream2_get_bytes_left(&s->gb) < n_blocks * 4)
184 return AVERROR_INVALIDDATA;
185 while (n_blocks--) {
186 CHECK_BLOCK();
187 block_ptr = row_ptr + pixel_ptr;
188 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
189 uint8_t index = bytestream2_get_byteu(&s->gb);
190 for (pixel_x = 0; pixel_x < 4; pixel_x++){
191 uint8_t 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 if (bytestream2_get_bytes_left(&s->gb) < 30)
204 return AVERROR_INVALIDDATA;
205 CHECK_BLOCK();
206 block_ptr = row_ptr + pixel_ptr;
207 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
208 for (pixel_x = 0; pixel_x < 4; pixel_x++){
209 /* We already have color of upper left pixel */
210 if ((pixel_y != 0) || (pixel_x != 0))
211 colorA = bytestream2_get_be16u(&s->gb);
212 pixels[block_ptr] = colorA;
213 block_ptr++;
214 }
215 block_ptr += row_inc;
216 }
217 ADVANCE_BLOCK();
218 break;
219
220 /* Unknown opcode */
221 default:
222 av_log(s->avctx, AV_LOG_ERROR, "Unknown opcode %d in rpza chunk."
223 " Skip remaining %d bytes of chunk data.\n", opcode,
224 bytestream2_get_bytes_left(&s->gb));
225 return AVERROR_INVALIDDATA;
226 } /* Opcode switch */
227 }
228
229 return 0;
230 }
231
232 static av_cold int rpza_decode_init(AVCodecContext *avctx)
233 {
234 RpzaContext *s = avctx->priv_data;
235
236 s->avctx = avctx;
237 avctx->pix_fmt = AV_PIX_FMT_RGB555;
238
239 s->frame = av_frame_alloc();
240 if (!s->frame)
241 return AVERROR(ENOMEM);
242
243 return 0;
244 }
245
246 static int rpza_decode_frame(AVCodecContext *avctx,
247 void *data, int *got_frame,
248 AVPacket *avpkt)
249 {
250 RpzaContext *s = avctx->priv_data;
251 int ret;
252
253 bytestream2_init(&s->gb, avpkt->data, avpkt->size);
254
255 if ((ret = ff_reget_buffer(avctx, s->frame)) < 0) {
256 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
257 return ret;
258 }
259
260 ret = rpza_decode_stream(s);
261 if (ret < 0)
262 return ret;
263
264 if ((ret = av_frame_ref(data, s->frame)) < 0)
265 return ret;
266
267 *got_frame = 1;
268
269 /* always report that the buffer was completely consumed */
270 return avpkt->size;
271 }
272
273 static av_cold int rpza_decode_end(AVCodecContext *avctx)
274 {
275 RpzaContext *s = avctx->priv_data;
276
277 av_frame_free(&s->frame);
278
279 return 0;
280 }
281
282 AVCodec ff_rpza_decoder = {
283 .name = "rpza",
284 .long_name = NULL_IF_CONFIG_SMALL("QuickTime video (RPZA)"),
285 .type = AVMEDIA_TYPE_VIDEO,
286 .id = AV_CODEC_ID_RPZA,
287 .priv_data_size = sizeof(RpzaContext),
288 .init = rpza_decode_init,
289 .close = rpza_decode_end,
290 .decode = rpza_decode_frame,
291 .capabilities = AV_CODEC_CAP_DR1,
292 };