1/*
2 * Delphine Software International CIN video decoder
3 * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
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 * Delphine Software International CIN video decoder
25 */
26
27#include "avcodec.h"
28#include "bytestream.h"
29#include "internal.h"
30
31typedef enum CinVideoBitmapIndex {
32    CIN_CUR_BMP = 0, /* current */
33    CIN_PRE_BMP = 1, /* previous */
34    CIN_INT_BMP = 2  /* intermediate */
35} CinVideoBitmapIndex;
36
37typedef struct CinVideoContext {
38    AVCodecContext *avctx;
39    AVFrame *frame;
40    unsigned int bitmap_size;
41    uint32_t palette[256];
42    uint8_t *bitmap_table[3];
43} CinVideoContext;
44
45static av_cold void destroy_buffers(CinVideoContext *cin)
46{
47    int i;
48
49    for (i = 0; i < 3; ++i)
50        av_freep(&cin->bitmap_table[i]);
51}
52
53static av_cold int allocate_buffers(CinVideoContext *cin)
54{
55    int i;
56
57    for (i = 0; i < 3; ++i) {
58        cin->bitmap_table[i] = av_mallocz(cin->bitmap_size);
59        if (!cin->bitmap_table[i]) {
60            av_log(cin->avctx, AV_LOG_ERROR, "Can't allocate bitmap buffers.\n");
61            destroy_buffers(cin);
62            return AVERROR(ENOMEM);
63        }
64    }
65
66    return 0;
67}
68
69static av_cold int cinvideo_decode_init(AVCodecContext *avctx)
70{
71    CinVideoContext *cin = avctx->priv_data;
72
73    cin->avctx = avctx;
74    avctx->pix_fmt = AV_PIX_FMT_PAL8;
75
76    cin->frame = av_frame_alloc();
77    if (!cin->frame)
78        return AVERROR(ENOMEM);
79
80    cin->bitmap_size = avctx->width * avctx->height;
81    if (allocate_buffers(cin))
82        return AVERROR(ENOMEM);
83
84    return 0;
85}
86
87static void cin_apply_delta_data(const unsigned char *src, unsigned char *dst,
88                                 int size)
89{
90    while (size--)
91        *dst++ += *src++;
92}
93
94static int cin_decode_huffman(const unsigned char *src, int src_size,
95                              unsigned char *dst, int dst_size)
96{
97    int b, huff_code = 0;
98    unsigned char huff_code_table[15];
99    unsigned char *dst_cur       = dst;
100    unsigned char *dst_end       = dst + dst_size;
101    const unsigned char *src_end = src + src_size;
102
103    memcpy(huff_code_table, src, 15);
104    src += 15;
105
106    while (src < src_end) {
107        huff_code = *src++;
108        if ((huff_code >> 4) == 15) {
109            b          = huff_code << 4;
110            huff_code  = *src++;
111            *dst_cur++ = b | (huff_code >> 4);
112        } else
113            *dst_cur++ = huff_code_table[huff_code >> 4];
114        if (dst_cur >= dst_end)
115            break;
116
117        huff_code &= 15;
118        if (huff_code == 15) {
119            *dst_cur++ = *src++;
120        } else
121            *dst_cur++ = huff_code_table[huff_code];
122        if (dst_cur >= dst_end)
123            break;
124    }
125
126    return dst_cur - dst;
127}
128
129static int cin_decode_lzss(const unsigned char *src, int src_size,
130                           unsigned char *dst, int dst_size)
131{
132    uint16_t cmd;
133    int i, sz, offset, code;
134    unsigned char *dst_end       = dst + dst_size, *dst_start = dst;
135    const unsigned char *src_end = src + src_size;
136
137    while (src < src_end && dst < dst_end) {
138        code = *src++;
139        for (i = 0; i < 8 && src < src_end && dst < dst_end; ++i) {
140            if (code & (1 << i)) {
141                *dst++ = *src++;
142            } else {
143                cmd    = AV_RL16(src);
144                src   += 2;
145                offset = cmd >> 4;
146                if ((int)(dst - dst_start) < offset + 1)
147                    return AVERROR_INVALIDDATA;
148                sz = (cmd & 0xF) + 2;
149                /* don't use memcpy/memmove here as the decoding routine
150                 * (ab)uses buffer overlappings to repeat bytes in the
151                 * destination */
152                sz = FFMIN(sz, dst_end - dst);
153                while (sz--) {
154                    *dst = *(dst - offset - 1);
155                    ++dst;
156                }
157            }
158        }
159    }
160
161    return 0;
162}
163
164static int cin_decode_rle(const unsigned char *src, int src_size,
165                           unsigned char *dst, int dst_size)
166{
167    int len, code;
168    unsigned char *dst_end       = dst + dst_size;
169    const unsigned char *src_end = src + src_size;
170
171    while (src + 1 < src_end && dst < dst_end) {
172        code = *src++;
173        if (code & 0x80) {
174            len = code - 0x7F;
175            memset(dst, *src++, FFMIN(len, dst_end - dst));
176        } else {
177            len = code + 1;
178            if (len > src_end-src) {
179                av_log(NULL, AV_LOG_ERROR, "RLE overread\n");
180                return AVERROR_INVALIDDATA;
181            }
182            memcpy(dst, src, FFMIN3(len, dst_end - dst, src_end - src));
183            src += len;
184        }
185        dst += len;
186    }
187    return 0;
188}
189
190static int cinvideo_decode_frame(AVCodecContext *avctx,
191                                 void *data, int *got_frame,
192                                 AVPacket *avpkt)
193{
194    const uint8_t *buf   = avpkt->data;
195    int buf_size         = avpkt->size;
196    CinVideoContext *cin = avctx->priv_data;
197    int i, y, palette_type, palette_colors_count,
198        bitmap_frame_type, bitmap_frame_size, res = 0;
199
200    palette_type         = buf[0];
201    palette_colors_count = AV_RL16(buf + 1);
202    bitmap_frame_type    = buf[3];
203    buf                 += 4;
204
205    bitmap_frame_size = buf_size - 4;
206
207    /* handle palette */
208    if (bitmap_frame_size < palette_colors_count * (3 + (palette_type != 0)))
209        return AVERROR_INVALIDDATA;
210    if (palette_type == 0) {
211        if (palette_colors_count > 256)
212            return AVERROR_INVALIDDATA;
213        for (i = 0; i < palette_colors_count; ++i) {
214            cin->palette[i]    = 0xFFU << 24 | bytestream_get_le24(&buf);
215            bitmap_frame_size -= 3;
216        }
217    } else {
218        for (i = 0; i < palette_colors_count; ++i) {
219            cin->palette[buf[0]] = 0xFFU << 24 | AV_RL24(buf + 1);
220            buf                 += 4;
221            bitmap_frame_size   -= 4;
222        }
223    }
224
225    /* note: the decoding routines below assumes that
226     * surface.width = surface.pitch */
227    switch (bitmap_frame_type) {
228    case 9:
229        cin_decode_rle(buf, bitmap_frame_size,
230                       cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
231        break;
232    case 34:
233        cin_decode_rle(buf, bitmap_frame_size,
234                       cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
235        cin_apply_delta_data(cin->bitmap_table[CIN_PRE_BMP],
236                             cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
237        break;
238    case 35:
239        bitmap_frame_size = cin_decode_huffman(buf, bitmap_frame_size,
240                           cin->bitmap_table[CIN_INT_BMP], cin->bitmap_size);
241        cin_decode_rle(cin->bitmap_table[CIN_INT_BMP], bitmap_frame_size,
242                       cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
243        break;
244    case 36:
245        bitmap_frame_size = cin_decode_huffman(buf, bitmap_frame_size,
246                                               cin->bitmap_table[CIN_INT_BMP],
247                                               cin->bitmap_size);
248        cin_decode_rle(cin->bitmap_table[CIN_INT_BMP], bitmap_frame_size,
249                       cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
250        cin_apply_delta_data(cin->bitmap_table[CIN_PRE_BMP],
251                             cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
252        break;
253    case 37:
254        cin_decode_huffman(buf, bitmap_frame_size,
255                           cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
256        break;
257    case 38:
258        res = cin_decode_lzss(buf, bitmap_frame_size,
259                              cin->bitmap_table[CIN_CUR_BMP],
260                              cin->bitmap_size);
261        if (res < 0)
262            return res;
263        break;
264    case 39:
265        res = cin_decode_lzss(buf, bitmap_frame_size,
266                              cin->bitmap_table[CIN_CUR_BMP],
267                              cin->bitmap_size);
268        if (res < 0)
269            return res;
270        cin_apply_delta_data(cin->bitmap_table[CIN_PRE_BMP],
271                             cin->bitmap_table[CIN_CUR_BMP], cin->bitmap_size);
272        break;
273    }
274
275    if ((res = ff_reget_buffer(avctx, cin->frame)) < 0)
276        return res;
277
278    memcpy(cin->frame->data[1], cin->palette, sizeof(cin->palette));
279    cin->frame->palette_has_changed = 1;
280    for (y = 0; y < cin->avctx->height; ++y)
281        memcpy(cin->frame->data[0] + (cin->avctx->height - 1 - y) * cin->frame->linesize[0],
282               cin->bitmap_table[CIN_CUR_BMP] + y * cin->avctx->width,
283               cin->avctx->width);
284
285    FFSWAP(uint8_t *, cin->bitmap_table[CIN_CUR_BMP],
286                      cin->bitmap_table[CIN_PRE_BMP]);
287
288    if ((res = av_frame_ref(data, cin->frame)) < 0)
289        return res;
290
291    *got_frame = 1;
292
293    return buf_size;
294}
295
296static av_cold int cinvideo_decode_end(AVCodecContext *avctx)
297{
298    CinVideoContext *cin = avctx->priv_data;
299
300    av_frame_free(&cin->frame);
301
302    destroy_buffers(cin);
303
304    return 0;
305}
306
307AVCodec ff_dsicinvideo_decoder = {
308    .name           = "dsicinvideo",
309    .long_name      = NULL_IF_CONFIG_SMALL("Delphine Software International CIN video"),
310    .type           = AVMEDIA_TYPE_VIDEO,
311    .id             = AV_CODEC_ID_DSICINVIDEO,
312    .priv_data_size = sizeof(CinVideoContext),
313    .init           = cinvideo_decode_init,
314    .close          = cinvideo_decode_end,
315    .decode         = cinvideo_decode_frame,
316    .capabilities   = CODEC_CAP_DR1,
317};
318