2 * Feeble Files/ScummVM DXA decoder
3 * Copyright (c) 2007 Konstantin Shishkov
5 * This file is part of Libav.
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.
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.
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
30 #include "libavutil/common.h"
31 #include "libavutil/intreadwrite.h"
40 typedef struct DxaDecContext {
48 static const int shift1[6] = { 0, 8, 8, 8, 4, 4 };
49 static const int shift2[6] = { 0, 0, 8, 4, 0, 4 };
51 static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
52 int stride, uint8_t *src, uint8_t *ref)
54 uint8_t *code, *data, *mv, *msk, *tmp, *tmp2;
56 int type, x, y, d, d2;
60 data = code + ((avctx->width * avctx->height) >> 4);
61 mv = data + AV_RB32(src + 0);
62 msk = mv + AV_RB32(src + 4);
64 for(j = 0; j < avctx->height; j += 4){
65 for(i = 0; i < avctx->width; i += 4){
70 case 4: // motion compensation
71 x = (*mv) >> 4; if(x & 8) x = 8 - x;
72 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
75 case 5: // skip in method 12
76 for(y = 0; y < 4; y++){
82 case 1: // masked change
83 case 10: // masked change with only half of pixels changed
84 case 11: // cases 10-15 are for method 12 only
94 mask = ((msk[0] & 0xF0) << shift1[type]) | ((msk[0] & 0xF) << shift2[type]);
97 for(y = 0; y < 4; y++){
98 for(x = 0; x < 4; x++){
99 tmp[x] = (mask & 0x8000) ? *data++ : tmp2[x];
106 case 2: // fill block
107 for(y = 0; y < 4; y++){
108 memset(tmp, data[0], 4);
114 for(y = 0; y < 4; y++){
115 memcpy(tmp, data, 4);
120 case 8: // subblocks - method 13 only
122 for(k = 0; k < 4; k++){
123 d = ((k & 1) << 1) + ((k & 2) * stride);
124 d2 = ((k & 1) << 1) + ((k & 2) * stride);
127 case 0x80: // motion compensation
128 x = (*mv) >> 4; if(x & 8) x = 8 - x;
129 y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
130 tmp2 += x + y*stride;
132 tmp[d + 0 ] = tmp2[0];
133 tmp[d + 1 ] = tmp2[1];
134 tmp[d + 0 + stride] = tmp2[0 + stride];
135 tmp[d + 1 + stride] = tmp2[1 + stride];
138 tmp[d + 0 ] = data[0];
139 tmp[d + 1 ] = data[0];
140 tmp[d + 0 + stride] = data[0];
141 tmp[d + 1 + stride] = data[0];
145 tmp[d + 0 ] = *data++;
146 tmp[d + 1 ] = *data++;
147 tmp[d + 0 + stride] = *data++;
148 tmp[d + 1 + stride] = *data++;
154 case 32: // vector quantization - 2 colors
157 for(y = 0; y < 4; y++){
158 for(x = 0; x < 4; x++){
159 tmp[x] = data[mask & 1];
167 case 33: // vector quantization - 3 or 4 colors
171 for(y = 0; y < 4; y++){
172 for(x = 0; x < 4; x++){
173 tmp[x] = data[mask & 3];
182 av_log(avctx, AV_LOG_ERROR, "Unknown opcode %d\n", type);
183 return AVERROR_INVALIDDATA;
192 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
194 AVFrame *frame = data;
195 const uint8_t *buf = avpkt->data;
196 int buf_size = avpkt->size;
197 DxaDecContext * const c = avctx->priv_data;
198 uint8_t *outptr, *srcptr, *tmpptr;
200 int i, j, compr, ret;
202 int orig_buf_size = buf_size;
205 /* make the palette available on the way out */
206 if(buf[0]=='C' && buf[1]=='M' && buf[2]=='A' && buf[3]=='P'){
210 for(i = 0; i < 256; i++){
214 c->pal[i] = (r << 16) | (g << 8) | b;
220 if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) {
221 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
224 memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
225 frame->palette_has_changed = pc;
227 outptr = frame->data[0];
228 srcptr = c->decomp_buf;
229 tmpptr = c->prev->data[0];
230 stride = frame->linesize[0];
232 if(buf[0]=='N' && buf[1]=='U' && buf[2]=='L' && buf[3]=='L')
238 if((compr != 4 && compr != -1) && uncompress(c->decomp_buf, &dsize, buf + 9, buf_size - 9) != Z_OK){
239 av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
240 return AVERROR_UNKNOWN;
244 frame->key_frame = 0;
245 frame->pict_type = AV_PICTURE_TYPE_P;
246 if (c->prev->data[0])
247 memcpy(frame->data[0], c->prev->data[0], frame->linesize[0] * avctx->height);
248 else{ // Should happen only when first frame is 'NULL'
249 memset(frame->data[0], 0, frame->linesize[0] * avctx->height);
250 frame->key_frame = 1;
251 frame->pict_type = AV_PICTURE_TYPE_I;
256 frame->key_frame = 1;
257 frame->pict_type = AV_PICTURE_TYPE_I;
258 for (j = 0; j < avctx->height; j++) {
259 memcpy(outptr, srcptr, avctx->width);
261 srcptr += avctx->width;
267 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
268 return AVERROR_INVALIDDATA;
270 frame->key_frame = 0;
271 frame->pict_type = AV_PICTURE_TYPE_P;
272 for (j = 0; j < avctx->height; j++) {
273 for (i = 0; i < avctx->width; i++)
274 outptr[i] = srcptr[i] ^ tmpptr[i];
277 srcptr += avctx->width;
280 case 12: // ScummVM coding
282 frame->key_frame = 0;
283 frame->pict_type = AV_PICTURE_TYPE_P;
284 decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, c->prev->data[0]);
287 av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", buf[4]);
288 return AVERROR_INVALIDDATA;
291 av_frame_unref(c->prev);
292 if ((ret = av_frame_ref(c->prev, frame)) < 0)
297 /* always report that the buffer was completely consumed */
298 return orig_buf_size;
301 static av_cold int decode_init(AVCodecContext *avctx)
303 DxaDecContext * const c = avctx->priv_data;
305 c->prev = av_frame_alloc();
307 return AVERROR(ENOMEM);
309 avctx->pix_fmt = AV_PIX_FMT_PAL8;
311 c->dsize = avctx->width * avctx->height * 2;
312 if((c->decomp_buf = av_malloc(c->dsize)) == NULL) {
313 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
314 return AVERROR(ENOMEM);
320 static av_cold int decode_end(AVCodecContext *avctx)
322 DxaDecContext * const c = avctx->priv_data;
324 av_freep(&c->decomp_buf);
325 av_frame_free(&c->prev);
330 AVCodec ff_dxa_decoder = {
332 .long_name = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),
333 .type = AVMEDIA_TYPE_VIDEO,
334 .id = AV_CODEC_ID_DXA,
335 .priv_data_size = sizeof(DxaDecContext),
338 .decode = decode_frame,
339 .capabilities = CODEC_CAP_DR1,