GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/dxa.c Lines: 187 222 84.2 %
Date: 2019-11-20 04:07:19 Branches: 90 121 74.4 %

Line Branch Exec Source
1
/*
2
 * Feeble Files/ScummVM DXA decoder
3
 * Copyright (c) 2007 Konstantin Shishkov
4
 *
5
 * This file is part of FFmpeg.
6
 *
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.
11
 *
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.
16
 *
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
20
 */
21
22
/**
23
 * @file
24
 * DXA Video decoder
25
 */
26
27
#include <stdio.h>
28
#include <stdlib.h>
29
30
#include "libavutil/common.h"
31
#include "libavutil/intreadwrite.h"
32
#include "bytestream.h"
33
#include "avcodec.h"
34
#include "internal.h"
35
36
#include <zlib.h>
37
38
/*
39
 * Decoder context
40
 */
41
typedef struct DxaDecContext {
42
    AVFrame *prev;
43
44
    int dsize;
45
#define DECOMP_BUF_PADDING 16
46
    uint8_t *decomp_buf;
47
    uint32_t pal[256];
48
} DxaDecContext;
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50
static const int shift1[6] = { 0, 8, 8, 8, 4, 4 };
51
static const int shift2[6] = { 0, 0, 8, 4, 0, 4 };
52
53
5
static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst,
54
                     int stride, uint8_t *src, int srcsize, uint8_t *ref)
55
{
56
    uint8_t *code, *data, *mv, *msk, *tmp, *tmp2;
57
5
    uint8_t *src_end = src + srcsize;
58
    int i, j, k;
59
    int type, x, y, d, d2;
60
    uint32_t mask;
61
62
5
    if (12ULL  + ((avctx->width * avctx->height) >> 4) + AV_RB32(src + 0) + AV_RB32(src + 4) > srcsize)
63
        return AVERROR_INVALIDDATA;
64
65
5
    code = src  + 12;
66
5
    data = code + ((avctx->width * avctx->height) >> 4);
67
5
    mv   = data + AV_RB32(src + 0);
68
5
    msk  = mv   + AV_RB32(src + 4);
69
70
255
    for(j = 0; j < avctx->height; j += 4){
71
40250
        for(i = 0; i < avctx->width; i += 4){
72

40000
            if (data > src_end || mv > src_end || msk > src_end)
73
                return AVERROR_INVALIDDATA;
74
40000
            tmp  = dst + i;
75
40000
            tmp2 = ref + i;
76
40000
            type = *code++;
77


40000
            switch(type){
78
227
            case 4: // motion compensation
79
227
                x = (*mv) >> 4;    if(x & 8) x = 8 - x;
80
227
                y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
81

227
                if (i < -x || avctx->width  - i - 4 < x ||
82

227
                    j < -y || avctx->height - j - 4 < y) {
83
                    av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y);
84
                    return AVERROR_INVALIDDATA;
85
                }
86
227
                tmp2 += x + y*stride;
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26615
            case 0: // skip
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            case 5: // skip in method 12
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133075
                for(y = 0; y < 4; y++){
90
106460
                    memcpy(tmp, tmp2, 4);
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106460
                    tmp  += stride;
92
106460
                    tmp2 += stride;
93
                }
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26615
                break;
95
326
            case 1:  // masked change
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            case 10: // masked change with only half of pixels changed
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            case 11: // cases 10-15 are for method 12 only
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            case 12:
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            case 13:
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            case 14:
101
            case 15:
102
326
                if(type == 1){
103
326
                    mask = AV_RB16(msk);
104
326
                    msk += 2;
105
                }else{
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                    type -= 10;
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                    mask = ((msk[0] & 0xF0) << shift1[type]) | ((msk[0] & 0xF) << shift2[type]);
108
                    msk++;
109
                }
110
1630
                for(y = 0; y < 4; y++){
111
6520
                    for(x = 0; x < 4; x++){
112
5216
                        tmp[x] = (mask & 0x8000) ? *data++ : tmp2[x];
113
5216
                        mask <<= 1;
114
                    }
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1304
                    tmp  += stride;
116
1304
                    tmp2 += stride;
117
                }
118
326
                break;
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2428
            case 2: // fill block
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12140
                for(y = 0; y < 4; y++){
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9712
                    memset(tmp, data[0], 4);
122
9712
                    tmp += stride;
123
                }
124
2428
                data++;
125
2428
                break;
126
705
            case 3: // raw block
127
3525
                for(y = 0; y < 4; y++){
128
2820
                    memcpy(tmp, data, 4);
129
2820
                    data += 4;
130
2820
                    tmp  += stride;
131
                }
132
705
                break;
133
681
            case 8: // subblocks - method 13 only
134
681
                mask = *msk++;
135
3405
                for(k = 0; k < 4; k++){
136
2724
                    d  = ((k & 1) << 1) + ((k & 2) * stride);
137
2724
                    d2 = ((k & 1) << 1) + ((k & 2) * stride);
138
2724
                    tmp2 = ref + i + d2;
139

2724
                    switch(mask & 0xC0){
140
361
                    case 0x80: // motion compensation
141
361
                        x = (*mv) >> 4;    if(x & 8) x = 8 - x;
142
361
                        y = (*mv++) & 0xF; if(y & 8) y = 8 - y;
143

361
                        if (i + 2*(k & 1) < -x || avctx->width  - i - 2*(k & 1) - 2 < x ||
144

361
                            j +   (k & 2) < -y || avctx->height - j -   (k & 2) - 2 < y) {
145
                            av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y);
146
                            return AVERROR_INVALIDDATA;
147
                        }
148
361
                        tmp2 += x + y*stride;
149
1446
                    case 0x00: // skip
150
1446
                        tmp[d + 0         ] = tmp2[0];
151
1446
                        tmp[d + 1         ] = tmp2[1];
152
1446
                        tmp[d + 0 + stride] = tmp2[0 + stride];
153
1446
                        tmp[d + 1 + stride] = tmp2[1 + stride];
154
1446
                        break;
155
696
                    case 0x40: // fill
156
696
                        tmp[d + 0         ] = data[0];
157
696
                        tmp[d + 1         ] = data[0];
158
696
                        tmp[d + 0 + stride] = data[0];
159
696
                        tmp[d + 1 + stride] = data[0];
160
696
                        data++;
161
696
                        break;
162
582
                    case 0xC0: // raw
163
582
                        tmp[d + 0         ] = *data++;
164
582
                        tmp[d + 1         ] = *data++;
165
582
                        tmp[d + 0 + stride] = *data++;
166
582
                        tmp[d + 1 + stride] = *data++;
167
582
                        break;
168
                    }
169
2724
                    mask <<= 2;
170
                }
171
681
                break;
172
9229
            case 32: // vector quantization - 2 colors
173
9229
                mask = AV_RB16(msk);
174
9229
                msk += 2;
175
46145
                for(y = 0; y < 4; y++){
176
184580
                    for(x = 0; x < 4; x++){
177
147664
                        tmp[x] = data[mask & 1];
178
147664
                        mask >>= 1;
179
                    }
180
36916
                    tmp  += stride;
181
36916
                    tmp2 += stride;
182
                }
183
9229
                data += 2;
184
9229
                break;
185
16
            case 33: // vector quantization - 3 or 4 colors
186
            case 34:
187
16
                mask = AV_RB32(msk);
188
16
                msk += 4;
189
80
                for(y = 0; y < 4; y++){
190
320
                    for(x = 0; x < 4; x++){
191
256
                        tmp[x] = data[mask & 3];
192
256
                        mask >>= 2;
193
                    }
194
64
                    tmp  += stride;
195
64
                    tmp2 += stride;
196
                }
197
16
                data += type - 30;
198
16
                break;
199
            default:
200
                av_log(avctx, AV_LOG_ERROR, "Unknown opcode %d\n", type);
201
                return AVERROR_INVALIDDATA;
202
            }
203
        }
204
250
        dst += stride * 4;
205
250
        ref += stride * 4;
206
    }
207
5
    return 0;
208
}
209
210
33
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
211
{
212
33
    AVFrame *frame = data;
213
33
    DxaDecContext * const c = avctx->priv_data;
214
    uint8_t *outptr, *srcptr, *tmpptr;
215
    unsigned long dsize;
216
    int i, j, compr, ret;
217
    int stride;
218
33
    int pc = 0;
219
    GetByteContext gb;
220
221
33
    bytestream2_init(&gb, avpkt->data, avpkt->size);
222
223
    /* make the palette available on the way out */
224
33
    if (bytestream2_peek_le32(&gb) == MKTAG('C','M','A','P')) {
225
2
        bytestream2_skip(&gb, 4);
226
514
        for(i = 0; i < 256; i++){
227
512
            c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&gb);
228
        }
229
2
        pc = 1;
230
    }
231
232
33
    if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
233
        return ret;
234
33
    memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
235
33
    frame->palette_has_changed = pc;
236
237
33
    outptr = frame->data[0];
238
33
    srcptr = c->decomp_buf;
239
33
    tmpptr = c->prev->data[0];
240
33
    stride = frame->linesize[0];
241
242
33
    if (bytestream2_get_le32(&gb) == MKTAG('N','U','L','L'))
243
16
        compr = -1;
244
    else
245
17
        compr = bytestream2_get_byte(&gb);
246
247
33
    dsize = c->dsize;
248

33
    if (compr != 4 && compr != -1) {
249
17
        bytestream2_skip(&gb, 4);
250
17
        if (uncompress(c->decomp_buf, &dsize, avpkt->data + bytestream2_tell(&gb),
251
17
                       bytestream2_get_bytes_left(&gb)) != Z_OK) {
252
            av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n");
253
            return AVERROR_UNKNOWN;
254
        }
255
17
        memset(c->decomp_buf + dsize, 0, DECOMP_BUF_PADDING);
256
    }
257
258
33
    if (avctx->debug & FF_DEBUG_PICT_INFO)
259
        av_log(avctx, AV_LOG_DEBUG, "compr:%2d, dsize:%d\n", compr, (int)dsize);
260
261

33
    switch(compr){
262
16
    case -1:
263
16
        frame->key_frame = 0;
264
16
        frame->pict_type = AV_PICTURE_TYPE_P;
265
16
        if (c->prev->data[0])
266
16
            memcpy(frame->data[0], c->prev->data[0], frame->linesize[0] * avctx->height);
267
        else{ // Should happen only when first frame is 'NULL'
268
            memset(frame->data[0], 0, frame->linesize[0] * avctx->height);
269
            frame->key_frame = 1;
270
            frame->pict_type = AV_PICTURE_TYPE_I;
271
        }
272
16
        break;
273
2
    case 2:
274
    case 4:
275
2
        frame->key_frame = 1;
276
2
        frame->pict_type = AV_PICTURE_TYPE_I;
277
682
        for (j = 0; j < avctx->height; j++) {
278
680
                memcpy(outptr, srcptr, avctx->width);
279
680
            outptr += stride;
280
680
            srcptr += avctx->width;
281
        }
282
2
        break;
283
10
    case 3:
284
    case 5:
285
10
        if (!tmpptr) {
286
            av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
287
            if (!(avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
288
                return AVERROR_INVALIDDATA;
289
        }
290
10
        frame->key_frame = 0;
291
10
        frame->pict_type = AV_PICTURE_TYPE_P;
292
4810
        for (j = 0; j < avctx->height; j++) {
293
4800
            if(tmpptr){
294
3076800
                for(i = 0; i < avctx->width; i++)
295
3072000
                    outptr[i] = srcptr[i] ^ tmpptr[i];
296
4800
                tmpptr += stride;
297
            }else
298
                memcpy(outptr, srcptr, avctx->width);
299
4800
            outptr += stride;
300
4800
            srcptr += avctx->width;
301
        }
302
10
        break;
303
5
    case 12: // ScummVM coding
304
    case 13:
305
5
        frame->key_frame = 0;
306
5
        frame->pict_type = AV_PICTURE_TYPE_P;
307
5
        if (!c->prev->data[0]) {
308
            av_log(avctx, AV_LOG_ERROR, "Missing reference frame\n");
309
            return AVERROR_INVALIDDATA;
310
        }
311
5
        decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, dsize, c->prev->data[0]);
312
5
        break;
313
    default:
314
        av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", compr);
315
        return AVERROR_INVALIDDATA;
316
    }
317
318
33
    av_frame_unref(c->prev);
319
33
    if ((ret = av_frame_ref(c->prev, frame)) < 0)
320
        return ret;
321
322
33
    *got_frame = 1;
323
324
    /* always report that the buffer was completely consumed */
325
33
    return avpkt->size;
326
}
327
328
5
static av_cold int decode_init(AVCodecContext *avctx)
329
{
330
5
    DxaDecContext * const c = avctx->priv_data;
331
332

5
    if (avctx->width%4 || avctx->height%4) {
333
        avpriv_request_sample(avctx, "dimensions are not a multiple of 4");
334
        return AVERROR_INVALIDDATA;
335
    }
336
337
5
    c->prev = av_frame_alloc();
338
5
    if (!c->prev)
339
        return AVERROR(ENOMEM);
340
341
5
    avctx->pix_fmt = AV_PIX_FMT_PAL8;
342
343
5
    c->dsize = avctx->width * avctx->height * 2;
344
5
    c->decomp_buf = av_malloc(c->dsize + DECOMP_BUF_PADDING);
345
5
    if (!c->decomp_buf) {
346
        av_frame_free(&c->prev);
347
        av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
348
        return AVERROR(ENOMEM);
349
    }
350
351
5
    return 0;
352
}
353
354
5
static av_cold int decode_end(AVCodecContext *avctx)
355
{
356
5
    DxaDecContext * const c = avctx->priv_data;
357
358
5
    av_freep(&c->decomp_buf);
359
5
    av_frame_free(&c->prev);
360
361
5
    return 0;
362
}
363
364
AVCodec ff_dxa_decoder = {
365
    .name           = "dxa",
366
    .long_name      = NULL_IF_CONFIG_SMALL("Feeble Files/ScummVM DXA"),
367
    .type           = AVMEDIA_TYPE_VIDEO,
368
    .id             = AV_CODEC_ID_DXA,
369
    .priv_data_size = sizeof(DxaDecContext),
370
    .init           = decode_init,
371
    .close          = decode_end,
372
    .decode         = decode_frame,
373
    .capabilities   = AV_CODEC_CAP_DR1,
374
};