1 /*
2 * Gryphon's Anim Compressor 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 #include "avcodec.h"
32 #include "bytestream.h"
33 #include "internal.h"
34
35 typedef struct ARBCContext {
36 GetByteContext gb;
37
38 AVFrame *prev_frame;
39 } ARBCContext;
40
fill_tile4(AVCodecContext * avctx,int color,AVFrame * frame)41 static int fill_tile4(AVCodecContext *avctx, int color, AVFrame *frame)
42 {
43 ARBCContext *s = avctx->priv_data;
44 GetByteContext *gb = &s->gb;
45 int nb_tiles = bytestream2_get_le16(gb);
46 int h = avctx->height - 1;
47 int pixels_overwritten = 0;
48
49 if ((avctx->width / 4 + 1) * (avctx->height / 4 + 1) < nb_tiles)
50 return 0;
51
52 for (int i = 0; i < nb_tiles; i++) {
53 int y = bytestream2_get_byte(gb);
54 int x = bytestream2_get_byte(gb);
55 uint16_t mask = bytestream2_get_le16(gb);
56 int start_y = y * 4, start_x = x * 4;
57 int end_y = start_y + 4, end_x = start_x + 4;
58
59 for (int j = start_y; j < end_y; j++) {
60 for (int k = start_x; k < end_x; k++) {
61 if (mask & 0x8000) {
62 if (j >= avctx->height || k >= avctx->width) {
63 mask = mask << 1;
64 continue;
65 }
66 AV_WB24(&frame->data[0][frame->linesize[0] * (h - j) + 3 * k], color);
67 pixels_overwritten ++;
68 }
69 mask = mask << 1;
70 }
71 }
72 }
73 return pixels_overwritten;
74 }
75
fill_tileX(AVCodecContext * avctx,int tile_width,int tile_height,int color,AVFrame * frame)76 static int fill_tileX(AVCodecContext *avctx, int tile_width, int tile_height,
77 int color, AVFrame *frame)
78 {
79 ARBCContext *s = avctx->priv_data;
80 GetByteContext *gb = &s->gb;
81 const int step_h = tile_height / 4;
82 const int step_w = tile_width / 4;
83 int nb_tiles = bytestream2_get_le16(gb);
84 int h = avctx->height - 1;
85 int pixels_overwritten = 0;
86
87 if ((avctx->width / tile_width + 1) * (avctx->height / tile_height + 1) < nb_tiles)
88 return 0;
89
90 for (int i = 0; i < nb_tiles; i++) {
91 int y = bytestream2_get_byte(gb);
92 int x = bytestream2_get_byte(gb);
93 uint16_t mask = bytestream2_get_le16(gb);
94 int start_y = y * tile_height, start_x = x * tile_width;
95 int end_y = start_y + tile_height, end_x = start_x + tile_width;
96
97 if (start_x >= avctx->width || start_y >= avctx->height)
98 continue;
99
100 for (int j = start_y; j < end_y; j += step_h) {
101 for (int k = start_x; k < end_x; k += step_w) {
102 if (mask & 0x8000U) {
103 for (int m = 0; m < step_h; m++) {
104 for (int n = 0; n < step_w; n++) {
105 if (j + m >= avctx->height || k + n >= avctx->width)
106 continue;
107 AV_WB24(&frame->data[0][frame->linesize[0] * (h - (j + m)) + 3 * (k + n)], color);
108 }
109 }
110 pixels_overwritten += FFMIN(step_h, avctx->height - j) * FFMIN(step_w, avctx->width - k);
111 }
112 mask = mask << 1;
113 }
114 }
115 }
116 return pixels_overwritten;
117 }
118
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)119 static int decode_frame(AVCodecContext *avctx, void *data,
120 int *got_frame, AVPacket *avpkt)
121 {
122 ARBCContext *s = avctx->priv_data;
123 AVFrame *frame = data;
124 int ret, nb_segments;
125 int prev_pixels = avctx->width * avctx->height;
126
127 if (avpkt->size < 10)
128 return AVERROR_INVALIDDATA;
129
130 bytestream2_init(&s->gb, avpkt->data, avpkt->size);
131 bytestream2_skip(&s->gb, 8);
132 nb_segments = bytestream2_get_le16(&s->gb);
133 if (nb_segments == 0)
134 return avpkt->size;
135
136 if (7 * nb_segments > bytestream2_get_bytes_left(&s->gb))
137 return AVERROR_INVALIDDATA;
138
139 if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
140 return ret;
141
142 if (s->prev_frame->data[0]) {
143 ret = av_frame_copy(frame, s->prev_frame);
144 if (ret < 0)
145 return ret;
146 }
147
148 for (int i = 0; i < nb_segments; i++) {
149 int resolution_flag;
150 int fill;
151
152 if (bytestream2_get_bytes_left(&s->gb) <= 0)
153 return AVERROR_INVALIDDATA;
154
155 fill = bytestream2_get_byte(&s->gb) << 16;
156 bytestream2_skip(&s->gb, 1);
157 fill |= bytestream2_get_byte(&s->gb) << 8;
158 bytestream2_skip(&s->gb, 1);
159 fill |= bytestream2_get_byte(&s->gb) << 0;
160 bytestream2_skip(&s->gb, 1);
161 resolution_flag = bytestream2_get_byte(&s->gb);
162
163 if (resolution_flag & 0x10)
164 prev_pixels -= fill_tileX(avctx, 1024, 1024, fill, frame);
165 if (resolution_flag & 0x08)
166 prev_pixels -= fill_tileX(avctx, 256, 256, fill, frame);
167 if (resolution_flag & 0x04)
168 prev_pixels -= fill_tileX(avctx, 64, 64, fill, frame);
169 if (resolution_flag & 0x02)
170 prev_pixels -= fill_tileX(avctx, 16, 16, fill, frame);
171 if (resolution_flag & 0x01)
172 prev_pixels -= fill_tile4(avctx, fill, frame);
173 }
174
175 av_frame_unref(s->prev_frame);
176 if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
177 return ret;
178
179 frame->pict_type = prev_pixels <= 0 ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
180 frame->key_frame = prev_pixels <= 0;
181 *got_frame = 1;
182
183 return avpkt->size;
184 }
185
decode_init(AVCodecContext * avctx)186 static av_cold int decode_init(AVCodecContext *avctx)
187 {
188 ARBCContext *s = avctx->priv_data;
189
190 avctx->pix_fmt = AV_PIX_FMT_RGB24;
191
192 s->prev_frame = av_frame_alloc();
193 if (!s->prev_frame)
194 return AVERROR(ENOMEM);
195
196 return 0;
197 }
198
decode_flush(AVCodecContext * avctx)199 static void decode_flush(AVCodecContext *avctx)
200 {
201 ARBCContext *s = avctx->priv_data;
202
203 av_frame_unref(s->prev_frame);
204 }
205
decode_close(AVCodecContext * avctx)206 static av_cold int decode_close(AVCodecContext *avctx)
207 {
208 ARBCContext *s = avctx->priv_data;
209
210 av_frame_free(&s->prev_frame);
211
212 return 0;
213 }
214
215 AVCodec ff_arbc_decoder = {
216 .name = "arbc",
217 .long_name = NULL_IF_CONFIG_SMALL("Gryphon's Anim Compressor"),
218 .type = AVMEDIA_TYPE_VIDEO,
219 .id = AV_CODEC_ID_ARBC,
220 .priv_data_size = sizeof(ARBCContext),
221 .init = decode_init,
222 .decode = decode_frame,
223 .flush = decode_flush,
224 .close = decode_close,
225 .capabilities = AV_CODEC_CAP_DR1,
226 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
227 };
228