2 * Feeble Files/ScummVM DXA decoder
3 * Copyright (c) 2007 Konstantin Shishkov
5 * This file is part of FFmpeg.
7 * FFmpeg 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.
12 * FFmpeg 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.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 #include "libavutil/common.h"
31 #include "libavutil/intreadwrite.h"
39 typedef struct DxaDecContext {
47 static const int shift1[6] = { 0, 8, 8, 8, 4, 4 };
48 static const int shift2[6] = { 0, 0, 8, 4, 0, 4 };
50 static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst, uint8_t *src, uint8_t *ref)
52 uint8_t *code, *data, *mv, *msk, *tmp, *tmp2;
54 int type, x, y, d, d2;
55 int stride = c->pic.linesize[0];
59 data = code + ((avctx->width * avctx->height) >> 4);
60 mv = data + AV_RB32(src + 0);
61 msk = mv + AV_RB32(src + 4);
63 for(j = 0; j < avctx->height; j += 4){
64 for(i = 0; i < avctx->width; i += 4){
69 case 4: // motion compensation
70 x = (*mv) >> 4; if(x & 8) x = 8 - x;
71 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
74 case 5: // skip in method 12
75 for(y = 0; y < 4; y++){
81 case 1: // masked change
82 case 10: // masked change with only half of pixels changed
83 case 11: // cases 10-15 are for method 12 only
93 mask = ((msk[0] & 0xF0) << shift1[type]) | ((msk[0] & 0xF) << shift2[type]);
96 for(y = 0; y < 4; y++){
97 for(x = 0; x < 4; x++){
98 tmp[x] = (mask & 0x8000) ? *data++ : tmp2[x];
105 case 2: // fill block
106 for(y = 0; y < 4; y++){
107 memset(tmp, data[0], 4);
113 for(y = 0; y < 4; y++){
114 memcpy(tmp, data, 4);
119 case 8: // subblocks - method 13 only
121 for(k = 0; k < 4; k++){
122 d = ((k & 1) << 1) + ((k & 2) * stride);
123 d2 = ((k & 1) << 1) + ((k & 2) * stride);
126 case 0x80: // motion compensation
127 x = (*mv) >> 4; if(x & 8) x = 8 - x;
128 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
129 tmp2 += x + y*stride;
131 tmp[d + 0 ] = tmp2[0];
132 tmp[d + 1 ] = tmp2[1];
133 tmp[d + 0 + stride] = tmp2[0 + stride];
134 tmp[d + 1 + stride] = tmp2[1 + stride];
137 tmp[d + 0 ] = data[0];
138 tmp[d + 1 ] = data[0];
139 tmp[d + 0 + stride] = data[0];
140 tmp[d + 1 + stride] = data[0];
144 tmp[d + 0 ] = *data++;
145 tmp[d + 1 ] = *data++;
146 tmp[d + 0 + stride] = *data++;
147 tmp[d + 1 + stride] = *data++;
153 case 32: // vector quantization - 2 colors
156 for(y = 0; y < 4; y++){
157 for(x = 0; x < 4; x++){
158 tmp[x] = data[mask & 1];
166 case 33: // vector quantization - 3 or 4 colors
170 for(y = 0; y < 4; y++){
171 for(x = 0; x < 4; x++){
172 tmp[x] = data[mask & 3];
181 av_log(avctx, AV_LOG_ERROR, "Unknown opcode %d\n", type);
191 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
193 const uint8_t *buf = avpkt->data;
194 int buf_size = avpkt->size;
195 DxaDecContext * const c = avctx->priv_data;
196 uint8_t *outptr, *srcptr, *tmpptr;
200 int orig_buf_size = buf_size;
203 /* make the palette available on the way out */
204 if(buf[0]=='C' && buf[1]=='M' && buf[2]=='A' && buf[3]=='P'){
208 for(i = 0; i < 256; i++){
212 c->pal[i] = 0xFFU << 24 | r << 16 | g << 8 | b;
218 if(avctx->get_buffer(avctx, &c->pic) < 0){
219 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
222 memcpy(c->pic.data[1], c->pal, AVPALETTE_SIZE);
223 c->pic.palette_has_changed = pc;
225 outptr = c->pic.data[0];
226 srcptr = c->decomp_buf;
227 tmpptr = c->prev.data[0];
228 stride = c->pic.linesize[0];
230 if(buf[0]=='N' && buf[1]=='U' && buf[2]=='L' && buf[3]=='L')
236 if((compr != 4 && compr != -1) && uncompress(c->decomp_buf, &dsize, buf + 9, buf_size - 9) != Z_OK){
237 av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
242 c->pic.key_frame = 0;
243 c->pic.pict_type = AV_PICTURE_TYPE_P;
245 memcpy(c->pic.data[0], c->prev.data[0], c->pic.linesize[0] * avctx->height);
246 else{ // Should happen only when first frame is 'NULL'
247 memset(c->pic.data[0], 0, c->pic.linesize[0] * avctx->height);
248 c->pic.key_frame = 1;
249 c->pic.pict_type = AV_PICTURE_TYPE_I;
256 c->pic.key_frame = !(compr & 1);
257 c->pic.pict_type = (compr & 1) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
258 for(j = 0; j < avctx->height; j++){
259 if((compr & 1) && tmpptr){
260 for(i = 0; i < avctx->width; i++)
261 outptr[i] = srcptr[i] ^ tmpptr[i];
264 memcpy(outptr, srcptr, avctx->width);
266 srcptr += avctx->width;
269 case 12: // ScummVM coding
271 c->pic.key_frame = 0;
272 c->pic.pict_type = AV_PICTURE_TYPE_P;
273 decode_13(avctx, c, c->pic.data[0], srcptr, c->prev.data[0]);
276 av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", buf[4]);
280 FFSWAP(AVFrame, c->pic, c->prev);
282 avctx->release_buffer(avctx, &c->pic);
284 *data_size = sizeof(AVFrame);
285 *(AVFrame*)data = c->prev;
287 /* always report that the buffer was completely consumed */
288 return orig_buf_size;
291 static av_cold int decode_init(AVCodecContext *avctx)
293 DxaDecContext * const c = avctx->priv_data;
295 avctx->pix_fmt = AV_PIX_FMT_PAL8;
297 avcodec_get_frame_defaults(&c->pic);
298 avcodec_get_frame_defaults(&c->prev);
300 c->dsize = avctx->width * avctx->height * 2;
301 if((c->decomp_buf = av_malloc(c->dsize)) == NULL) {
302 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
309 static av_cold int decode_end(AVCodecContext *avctx)
311 DxaDecContext * const c = avctx->priv_data;
313 av_freep(&c->decomp_buf);
315 avctx->release_buffer(avctx, &c->prev);
317 avctx->release_buffer(avctx, &c->pic);
322 AVCodec ff_dxa_decoder = {
324 .type = AVMEDIA_TYPE_VIDEO,
325 .id = AV_CODEC_ID_DXA,
326 .priv_data_size = sizeof(DxaDecContext),
329 .decode = decode_frame,
330 .capabilities = CODEC_CAP_DR1,
331 .long_name = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),