2 * Quicktime Video (RPZA) Video Decoder
3 * Copyright (C) 2003 the ffmpeg project
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.
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.
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
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/
27 * The RPZA decoder outputs RGB555 colorspace data.
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.
45 typedef struct RpzaContext {
47 AVCodecContext *avctx;
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) | \
62 #define ADVANCE_BLOCK() \
65 if (pixel_ptr >= width) \
68 row_ptr += stride * 4; \
71 if (total_blocks < 0) \
73 av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
78 static void rpza_decode_stream(RpzaContext *s)
80 int width = s->avctx->width;
81 int stride = s->frame.linesize[0] / 2;
82 int row_inc = stride - 4;
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];
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",
104 /* Get chunk size, ingnoring first byte */
105 chunk_size = BE_32(&s->buf[stream_ptr]) & 0x00FFFFFF;
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");
112 chunk_size = s->size;
114 /* Number of 4x4 blocks in frame. */
115 total_blocks = (s->avctx->width * s->avctx->height) / (4 * 4);
117 /* Process chunk data */
118 while (stream_ptr < chunk_size) {
119 opcode = s->buf[stream_ptr++]; /* Get opcode */
121 n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
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++]);
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
136 switch (opcode & 0xe0) {
145 /* Fill blocks with one color */
147 colorA = BE_16 (&s->buf[stream_ptr]);
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;
156 block_ptr += row_inc;
162 /* Fill blocks with 4 colors */
164 colorA = BE_16 (&s->buf[stream_ptr]);
167 colorB = BE_16 (&s->buf[stream_ptr]);
170 /* sort out the colors */
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;
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;
188 /* blue components */
191 color4[1] |= ((11 * ta + 21 * tb) >> 5);
192 color4[2] |= ((21 * ta + 11 * tb) >> 5);
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];
203 block_ptr += row_inc;
209 /* Fill block with 16 colors */
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]);
219 pixels[block_ptr] = colorA;
222 block_ptr += row_inc;
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);
233 } /* Opcode switch */
237 static int rpza_decode_init(AVCodecContext *avctx)
239 RpzaContext *s = (RpzaContext *)avctx->priv_data;
242 avctx->pix_fmt = PIX_FMT_RGB555;
243 avctx->has_b_frames = 0;
244 dsputil_init(&s->dsp, avctx);
246 s->frame.data[0] = NULL;
251 static int rpza_decode_frame(AVCodecContext *avctx,
252 void *data, int *data_size,
253 uint8_t *buf, int buf_size)
255 RpzaContext *s = (RpzaContext *)avctx->priv_data;
257 /* no supplementary picture */
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");
271 rpza_decode_stream(s);
273 *data_size = sizeof(AVFrame);
274 *(AVFrame*)data = s->frame;
276 /* always report that the buffer was completely consumed */
280 static int rpza_decode_end(AVCodecContext *avctx)
282 RpzaContext *s = (RpzaContext *)avctx->priv_data;
284 if (s->frame.data[0])
285 avctx->release_buffer(avctx, &s->frame);
290 AVCodec rpza_decoder = {