GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/midivid.c Lines: 0 147 0.0 %
Date: 2020-09-25 23:16:12 Branches: 0 80 0.0 %

Line Branch Exec Source
1
/*
2
 * MidiVid decoder
3
 * Copyright (c) 2019 Paul B Mahol
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
#include <stdio.h>
23
#include <stdlib.h>
24
#include <string.h>
25
26
#include "libavutil/imgutils.h"
27
#include "libavutil/internal.h"
28
#include "libavutil/intreadwrite.h"
29
#include "libavutil/mem.h"
30
31
#define BITSTREAM_READER_LE
32
#include "avcodec.h"
33
#include "get_bits.h"
34
#include "bytestream.h"
35
#include "internal.h"
36
37
typedef struct MidiVidContext {
38
    GetByteContext gb;
39
40
    uint8_t *uncompressed;
41
    unsigned int uncompressed_size;
42
    uint8_t *skip;
43
44
    AVFrame *frame;
45
} MidiVidContext;
46
47
static int decode_mvdv(MidiVidContext *s, AVCodecContext *avctx, AVFrame *frame)
48
{
49
    GetByteContext *gb = &s->gb;
50
    GetBitContext mask;
51
    GetByteContext idx9;
52
    uint16_t nb_vectors, intra_flag;
53
    const uint8_t *vec;
54
    const uint8_t *mask_start;
55
    uint8_t *skip;
56
    uint32_t mask_size;
57
    int idx9bits = 0;
58
    int idx9val = 0;
59
    uint32_t nb_blocks;
60
61
    nb_vectors = bytestream2_get_le16(gb);
62
    intra_flag = !!bytestream2_get_le16(gb);
63
    if (intra_flag) {
64
        nb_blocks = (avctx->width / 2) * (avctx->height / 2);
65
    } else {
66
        int ret, skip_linesize, padding;
67
68
        nb_blocks = bytestream2_get_le32(gb);
69
        skip_linesize = avctx->width >> 1;
70
        mask_start = gb->buffer_start + bytestream2_tell(gb);
71
        mask_size = (FFALIGN(avctx->width, 32) >> 2) * (avctx->height >> 2) >> 3;
72
        padding = (FFALIGN(avctx->width, 32) - avctx->width) >> 2;
73
74
        if (bytestream2_get_bytes_left(gb) < mask_size)
75
            return AVERROR_INVALIDDATA;
76
77
        ret = init_get_bits8(&mask, mask_start, mask_size);
78
        if (ret < 0)
79
            return ret;
80
        bytestream2_skip(gb, mask_size);
81
        skip = s->skip;
82
83
        for (int y = 0; y < avctx->height >> 2; y++) {
84
            for (int x = 0; x < avctx->width >> 2; x++) {
85
                int flag = !get_bits1(&mask);
86
87
                skip[(y*2)  *skip_linesize + x*2  ] = flag;
88
                skip[(y*2)  *skip_linesize + x*2+1] = flag;
89
                skip[(y*2+1)*skip_linesize + x*2  ] = flag;
90
                skip[(y*2+1)*skip_linesize + x*2+1] = flag;
91
            }
92
            skip_bits_long(&mask, padding);
93
        }
94
    }
95
96
    vec = gb->buffer_start + bytestream2_tell(gb);
97
    if (bytestream2_get_bytes_left(gb) < nb_vectors * 12)
98
        return AVERROR_INVALIDDATA;
99
    bytestream2_skip(gb, nb_vectors * 12);
100
    if (nb_vectors > 256) {
101
        if (bytestream2_get_bytes_left(gb) < (nb_blocks + 7 * !intra_flag) / 8)
102
            return AVERROR_INVALIDDATA;
103
        bytestream2_init(&idx9, gb->buffer_start + bytestream2_tell(gb), (nb_blocks + 7 * !intra_flag) / 8);
104
        bytestream2_skip(gb, (nb_blocks + 7 * !intra_flag) / 8);
105
    }
106
107
    skip = s->skip;
108
109
    for (int y = avctx->height - 2; y >= 0; y -= 2) {
110
        uint8_t *dsty = frame->data[0] + y * frame->linesize[0];
111
        uint8_t *dstu = frame->data[1] + y * frame->linesize[1];
112
        uint8_t *dstv = frame->data[2] + y * frame->linesize[2];
113
114
        for (int x = 0; x < avctx->width; x += 2) {
115
            int idx;
116
117
            if (!intra_flag && *skip++)
118
                continue;
119
            if (bytestream2_get_bytes_left(gb) <= 0)
120
                return AVERROR_INVALIDDATA;
121
            if (nb_vectors <= 256) {
122
                idx = bytestream2_get_byte(gb);
123
            } else {
124
                if (idx9bits == 0) {
125
                    idx9val = bytestream2_get_byte(&idx9);
126
                    idx9bits = 8;
127
                }
128
                idx9bits--;
129
                idx = bytestream2_get_byte(gb) | (((idx9val >> (7 - idx9bits)) & 1) << 8);
130
            }
131
            if (idx >= nb_vectors)
132
                return AVERROR_INVALIDDATA;
133
134
            dsty[x  +frame->linesize[0]] = vec[idx * 12 + 0];
135
            dsty[x+1+frame->linesize[0]] = vec[idx * 12 + 3];
136
            dsty[x]                      = vec[idx * 12 + 6];
137
            dsty[x+1]                    = vec[idx * 12 + 9];
138
139
            dstu[x  +frame->linesize[1]] = vec[idx * 12 + 1];
140
            dstu[x+1+frame->linesize[1]] = vec[idx * 12 + 4];
141
            dstu[x]                      = vec[idx * 12 + 7];
142
            dstu[x+1]                    = vec[idx * 12 +10];
143
144
            dstv[x  +frame->linesize[2]] = vec[idx * 12 + 2];
145
            dstv[x+1+frame->linesize[2]] = vec[idx * 12 + 5];
146
            dstv[x]                      = vec[idx * 12 + 8];
147
            dstv[x+1]                    = vec[idx * 12 +11];
148
        }
149
    }
150
151
    return intra_flag;
152
}
153
154
static ptrdiff_t lzss_uncompress(MidiVidContext *s, GetByteContext *gb, uint8_t *dst, unsigned int size)
155
{
156
    uint8_t *dst_start = dst;
157
    uint8_t *dst_end = dst + size;
158
159
    for (;bytestream2_get_bytes_left(gb) >= 3;) {
160
        int op = bytestream2_get_le16(gb);
161
162
        for (int i = 0; i < 16; i++) {
163
            if (op & 1) {
164
                int s0 = bytestream2_get_byte(gb);
165
                int s1 = bytestream2_get_byte(gb);
166
                int offset = ((s0 & 0xF0) << 4) | s1;
167
                int length = (s0 & 0xF) + 3;
168
169
                if (dst + length > dst_end ||
170
                    dst - offset < dst_start)
171
                    return AVERROR_INVALIDDATA;
172
                if (offset > 0) {
173
                    for (int j = 0; j < length; j++) {
174
                        dst[j] = dst[j - offset];
175
                    }
176
                }
177
                dst += length;
178
            } else {
179
                if (dst >= dst_end)
180
                    return AVERROR_INVALIDDATA;
181
                *dst++ = bytestream2_get_byte(gb);
182
            }
183
            op >>= 1;
184
        }
185
    }
186
187
    return dst - dst_start;
188
}
189
190
static int decode_frame(AVCodecContext *avctx, void *data,
191
                        int *got_frame, AVPacket *avpkt)
192
{
193
    MidiVidContext *s = avctx->priv_data;
194
    GetByteContext *gb = &s->gb;
195
    AVFrame *frame = s->frame;
196
    int ret, key, uncompressed;
197
198
    if (avpkt->size <= 13)
199
        return AVERROR_INVALIDDATA;
200
201
    bytestream2_init(gb, avpkt->data, avpkt->size);
202
    bytestream2_skip(gb, 8);
203
    uncompressed = bytestream2_get_le32(gb);
204
205
    if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
206
        return ret;
207
208
    if (uncompressed) {
209
        ret = decode_mvdv(s, avctx, frame);
210
    } else {
211
        av_fast_padded_malloc(&s->uncompressed, &s->uncompressed_size, 16LL * (avpkt->size - 12));
212
        if (!s->uncompressed)
213
            return AVERROR(ENOMEM);
214
215
        ret = lzss_uncompress(s, gb, s->uncompressed, s->uncompressed_size);
216
        if (ret < 0)
217
            return ret;
218
        bytestream2_init(gb, s->uncompressed, ret);
219
        ret = decode_mvdv(s, avctx, frame);
220
    }
221
222
    if (ret < 0)
223
        return ret;
224
    key = ret;
225
226
    if ((ret = av_frame_ref(data, s->frame)) < 0)
227
        return ret;
228
229
    frame->pict_type = key ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
230
    frame->key_frame = key;
231
    *got_frame = 1;
232
233
    return avpkt->size;
234
}
235
236
static av_cold int decode_init(AVCodecContext *avctx)
237
{
238
    MidiVidContext *s = avctx->priv_data;
239
    int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
240
241
    if (avctx->width & 3 || avctx->height & 3)
242
        ret = AVERROR_INVALIDDATA;
243
244
    if (ret < 0) {
245
        av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
246
               avctx->width, avctx->height);
247
        return ret;
248
    }
249
250
    avctx->pix_fmt = AV_PIX_FMT_YUV444P;
251
252
    s->frame = av_frame_alloc();
253
    if (!s->frame)
254
        return AVERROR(ENOMEM);
255
    s->skip = av_calloc(avctx->width >> 1, avctx->height >> 1);
256
    if (!s->skip)
257
        return AVERROR(ENOMEM);
258
259
    return 0;
260
}
261
262
static void decode_flush(AVCodecContext *avctx)
263
{
264
    MidiVidContext *s = avctx->priv_data;
265
266
    av_frame_unref(s->frame);
267
}
268
269
static av_cold int decode_close(AVCodecContext *avctx)
270
{
271
    MidiVidContext *s = avctx->priv_data;
272
273
    av_frame_free(&s->frame);
274
    av_freep(&s->uncompressed);
275
    av_freep(&s->skip);
276
277
    return 0;
278
}
279
280
AVCodec ff_mvdv_decoder = {
281
    .name           = "mvdv",
282
    .long_name      = NULL_IF_CONFIG_SMALL("MidiVid VQ"),
283
    .type           = AVMEDIA_TYPE_VIDEO,
284
    .id             = AV_CODEC_ID_MVDV,
285
    .priv_data_size = sizeof(MidiVidContext),
286
    .init           = decode_init,
287
    .decode         = decode_frame,
288
    .flush          = decode_flush,
289
    .close          = decode_close,
290
    .capabilities   = AV_CODEC_CAP_DR1,
291
    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
292
};