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 #include "internal.h"
30
31 typedef struct AnmContext {
32 AVFrame *frame;
33 int palette[AVPALETTE_COUNT];
34 } AnmContext;
35
decode_init(AVCodecContext * avctx)36 static av_cold int decode_init(AVCodecContext *avctx)
37 {
38 AnmContext *s = avctx->priv_data;
39 GetByteContext gb;
40 int i;
41
42 if (avctx->extradata_size < 16 * 8 + 4 * 256)
43 return AVERROR_INVALIDDATA;
44
45 avctx->pix_fmt = AV_PIX_FMT_PAL8;
46
47 s->frame = av_frame_alloc();
48 if (!s->frame)
49 return AVERROR(ENOMEM);
50
51 bytestream2_init(&gb, avctx->extradata, avctx->extradata_size);
52 bytestream2_skipu(&gb, 16 * 8);
53 for (i = 0; i < 256; i++)
54 s->palette[i] = (0xFFU << 24) | bytestream2_get_le32u(&gb);
55
56 return 0;
57 }
58
59 /**
60 * Perform decode operation
61 * @param dst pointer to destination image buffer
62 * @param dst_end pointer to end of destination image buffer
63 * @param gb GetByteContext (optional, see below)
64 * @param pixel Fill color (optional, see below)
65 * @param count Pixel count
66 * @param x Pointer to x-axis counter
67 * @param width Image width
68 * @param linesize Destination image buffer linesize
69 * @return non-zero if destination buffer is exhausted
70 *
71 * a copy operation is achieved when 'gb' is set
72 * a fill operation is achieved when 'gb' is null and pixel is >= 0
73 * a skip operation is achieved when 'gb' is null and pixel is < 0
74 */
op(uint8_t ** dst,const uint8_t * dst_end,GetByteContext * gb,int pixel,int count,int * x,int width,int linesize)75 static inline int op(uint8_t **dst, const uint8_t *dst_end,
76 GetByteContext *gb,
77 int pixel, int count,
78 int *x, int width, int linesize)
79 {
80 int remaining = width - *x;
81 while(count > 0) {
82 int striplen = FFMIN(count, remaining);
83 if (gb) {
84 if (bytestream2_get_bytes_left(gb) < striplen)
85 goto exhausted;
86 bytestream2_get_bufferu(gb, *dst, striplen);
87 } else if (pixel >= 0)
88 memset(*dst, pixel, striplen);
89 *dst += striplen;
90 remaining -= striplen;
91 count -= striplen;
92 if (remaining <= 0) {
93 *dst += linesize - width;
94 remaining = width;
95 }
96 if (linesize > 0) {
97 if (*dst >= dst_end) goto exhausted;
98 } else {
99 if (*dst <= dst_end) goto exhausted;
100 }
101 }
102 *x = width - remaining;
103 return 0;
104
105 exhausted:
106 *x = width - remaining;
107 return 1;
108 }
109
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)110 static int decode_frame(AVCodecContext *avctx,
111 void *data, int *got_frame,
112 AVPacket *avpkt)
113 {
114 AnmContext *s = avctx->priv_data;
115 const int buf_size = avpkt->size;
116 uint8_t *dst, *dst_end;
117 GetByteContext gb;
118 int count, ret, x = 0;
119
120 if (buf_size < 7)
121 return AVERROR_INVALIDDATA;
122
123 if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
124 return ret;
125 dst = s->frame->data[0];
126 dst_end = s->frame->data[0] + s->frame->linesize[0]*avctx->height;
127
128 bytestream2_init(&gb, avpkt->data, buf_size);
129
130 if (bytestream2_get_byte(&gb) != 0x42) {
131 avpriv_request_sample(avctx, "Unknown record type");
132 return AVERROR_INVALIDDATA;
133 }
134 if (bytestream2_get_byte(&gb)) {
135 avpriv_request_sample(avctx, "Padding bytes");
136 return AVERROR_PATCHWELCOME;
137 }
138 bytestream2_skip(&gb, 2);
139
140 do {
141 /* if statements are ordered by probability */
142 #define OP(gb, pixel, count) \
143 op(&dst, dst_end, (gb), (pixel), (count), &x, avctx->width, s->frame->linesize[0])
144
145 int type = bytestream2_get_byte(&gb);
146 count = type & 0x7F;
147 type >>= 7;
148 if (count) {
149 if (OP(type ? NULL : &gb, -1, count)) break;
150 } else if (!type) {
151 int pixel;
152 count = bytestream2_get_byte(&gb); /* count==0 gives nop */
153 pixel = bytestream2_get_byte(&gb);
154 if (OP(NULL, pixel, count)) break;
155 } else {
156 int pixel;
157 type = bytestream2_get_le16(&gb);
158 count = type & 0x3FFF;
159 type >>= 14;
160 if (!count) {
161 if (type == 0)
162 break; // stop
163 if (type == 2) {
164 avpriv_request_sample(avctx, "Unknown opcode");
165 return AVERROR_PATCHWELCOME;
166 }
167 continue;
168 }
169 pixel = type == 3 ? bytestream2_get_byte(&gb) : -1;
170 if (type == 1) count += 0x4000;
171 if (OP(type == 2 ? &gb : NULL, pixel, count)) break;
172 }
173 } while (bytestream2_get_bytes_left(&gb) > 0);
174
175 memcpy(s->frame->data[1], s->palette, AVPALETTE_SIZE);
176
177 *got_frame = 1;
178 if ((ret = av_frame_ref(data, s->frame)) < 0)
179 return ret;
180
181 return buf_size;
182 }
183
decode_end(AVCodecContext * avctx)184 static av_cold int decode_end(AVCodecContext *avctx)
185 {
186 AnmContext *s = avctx->priv_data;
187
188 av_frame_free(&s->frame);
189 return 0;
190 }
191
192 AVCodec ff_anm_decoder = {
193 .name = "anm",
194 .long_name = NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
195 .type = AVMEDIA_TYPE_VIDEO,
196 .id = AV_CODEC_ID_ANM,
197 .priv_data_size = sizeof(AnmContext),
198 .init = decode_init,
199 .close = decode_end,
200 .decode = decode_frame,
201 .capabilities = AV_CODEC_CAP_DR1,
202 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
203 };
204