1/*
2 * Deluxe Paint Animation decoder
3 * Copyright (c) 2009 Peter Ross
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 * Deluxe Paint Animation decoder
25 */
26
27#include "avcodec.h"
28#include "bytestream.h"
29
30typedef struct AnmContext {
31    AVFrame frame;
32    int x;  ///< x coordinate position
33} AnmContext;
34
35static av_cold int decode_init(AVCodecContext *avctx)
36{
37    AnmContext *s = avctx->priv_data;
38    const uint8_t *buf;
39    int i;
40
41    avctx->pix_fmt = PIX_FMT_PAL8;
42
43    if (avctx->extradata_size != 16*8 + 4*256)
44        return -1;
45
46    s->frame.reference = 1;
47    if (avctx->get_buffer(avctx, &s->frame) < 0) {
48        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
49        return -1;
50    }
51
52    buf = avctx->extradata + 16*8;
53    for (i = 0; i < 256; i++)
54        ((uint32_t*)s->frame.data[1])[i] = bytestream_get_le32(&buf);
55
56    return 0;
57}
58
59/**
60 * Perform decode operation
61 * @param dst, dst_end Destination image buffer
62 * @param buf, buf_end Source buffer (optional, see below)
63 * @param pixel Fill color (optional, see below)
64 * @param count Pixel count
65 * @param x Pointer to x-axis counter
66 * @param width Image width
67 * @param linesize Destination image buffer linesize
68 * @return non-zero if destination buffer is exhausted
69 *
70 * a copy operation is achieved when 'buf' is set
71 * a fill operation is acheived when 'buf' is null and pixel is >= 0
72 * a skip operation is acheived when 'buf' is null and pixel is < 0
73 */
74static inline int op(uint8_t **dst, const uint8_t *dst_end,
75                     const uint8_t **buf, const uint8_t *buf_end,
76                     int pixel, int count,
77                     int *x, int width, int linesize)
78{
79    int remaining = width - *x;
80    while(count > 0) {
81        int striplen = FFMIN(count, remaining);
82        if (buf) {
83            striplen = FFMIN(striplen, buf_end - *buf);
84            memcpy(*dst, *buf, striplen);
85            *buf += striplen;
86        } else if (pixel >= 0)
87            memset(*dst, pixel, striplen);
88        *dst      += striplen;
89        remaining -= striplen;
90        count     -= striplen;
91        if (remaining <= 0) {
92            *dst      += linesize - width;
93            remaining  = width;
94        }
95        if (linesize > 0) {
96            if (*dst >= dst_end) goto exhausted;
97        } else {
98            if (*dst <= dst_end) goto exhausted;
99        }
100    }
101    *x = width - remaining;
102    return 0;
103
104exhausted:
105    *x = width - remaining;
106    return 1;
107}
108
109static int decode_frame(AVCodecContext *avctx,
110                        void *data, int *data_size,
111                        AVPacket *avpkt)
112{
113    AnmContext *s = avctx->priv_data;
114    const uint8_t *buf = avpkt->data;
115    const int buf_size = avpkt->size;
116    const uint8_t *buf_end = buf + buf_size;
117    uint8_t *dst, *dst_end;
118    int count;
119
120    if(avctx->reget_buffer(avctx, &s->frame) < 0){
121        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
122        return -1;
123    }
124    dst     = s->frame.data[0];
125    dst_end = s->frame.data[0] + s->frame.linesize[0]*avctx->height;
126
127    if (buf[0] != 0x42) {
128        av_log_ask_for_sample(avctx, "unknown record type\n");
129        return buf_size;
130    }
131    if (buf[1]) {
132        av_log_ask_for_sample(avctx, "padding bytes not supported\n");
133        return buf_size;
134    }
135    buf += 4;
136
137    s->x = 0;
138    do {
139        /* if statements are ordered by probability */
140#define OP(buf, pixel, count) \
141    op(&dst, dst_end, (buf), buf_end, (pixel), (count), &s->x, avctx->width, s->frame.linesize[0])
142
143        int type = bytestream_get_byte(&buf);
144        count = type & 0x7F;
145        type >>= 7;
146        if (count) {
147            if (OP(type ? NULL : &buf, -1, count)) break;
148        } else if (!type) {
149            int pixel;
150            count = bytestream_get_byte(&buf);  /* count==0 gives nop */
151            pixel = bytestream_get_byte(&buf);
152            if (OP(NULL, pixel, count)) break;
153        } else {
154            int pixel;
155            type = bytestream_get_le16(&buf);
156            count = type & 0x3FFF;
157            type >>= 14;
158            if (!count) {
159                if (type == 0)
160                    break; // stop
161                if (type == 2) {
162                    av_log_ask_for_sample(avctx, "unknown opcode");
163                    return AVERROR_INVALIDDATA;
164                }
165                continue;
166            }
167            pixel = type == 3 ? bytestream_get_byte(&buf) : -1;
168            if (type == 1) count += 0x4000;
169            if (OP(type == 2 ? &buf : NULL, pixel, count)) break;
170        }
171    } while (buf + 1 < buf_end);
172
173    *data_size = sizeof(AVFrame);
174    *(AVFrame*)data = s->frame;
175    return buf_size;
176}
177
178static av_cold int decode_end(AVCodecContext *avctx)
179{
180    AnmContext *s = avctx->priv_data;
181    if (s->frame.data[0])
182        avctx->release_buffer(avctx, &s->frame);
183    return 0;
184}
185
186AVCodec anm_decoder = {
187    "anm",
188    AVMEDIA_TYPE_VIDEO,
189    CODEC_ID_ANM,
190    sizeof(AnmContext),
191    decode_init,
192    NULL,
193    decode_end,
194    decode_frame,
195    CODEC_CAP_DR1,
196    .long_name = NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
197};
198