• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 
30 #include "avcodec.h"
31 #include "bytestream.h"
32 #include "codec_internal.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,AVFrame * frame,int * got_frame,AVPacket * avpkt)119 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
120                         int *got_frame, AVPacket *avpkt)
121 {
122     ARBCContext *s = avctx->priv_data;
123     int ret, nb_segments;
124     int prev_pixels = avctx->width * avctx->height;
125 
126     if (avpkt->size < 10)
127         return AVERROR_INVALIDDATA;
128 
129     bytestream2_init(&s->gb, avpkt->data, avpkt->size);
130     bytestream2_skip(&s->gb, 8);
131     nb_segments = bytestream2_get_le16(&s->gb);
132     if (nb_segments == 0)
133         return avpkt->size;
134 
135     if (7 * nb_segments > bytestream2_get_bytes_left(&s->gb))
136         return AVERROR_INVALIDDATA;
137 
138     if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
139         return ret;
140 
141     if (s->prev_frame->data[0]) {
142         ret = av_frame_copy(frame, s->prev_frame);
143         if (ret < 0)
144             return ret;
145     }
146 
147     for (int i = 0; i < nb_segments; i++) {
148         int resolution_flag;
149         int fill;
150 
151         if (bytestream2_get_bytes_left(&s->gb) <= 0)
152             return AVERROR_INVALIDDATA;
153 
154         fill = bytestream2_get_byte(&s->gb) << 16;
155         bytestream2_skip(&s->gb, 1);
156         fill |= bytestream2_get_byte(&s->gb) << 8;
157         bytestream2_skip(&s->gb, 1);
158         fill |= bytestream2_get_byte(&s->gb) << 0;
159         bytestream2_skip(&s->gb, 1);
160         resolution_flag = bytestream2_get_byte(&s->gb);
161 
162         if (resolution_flag & 0x10)
163             prev_pixels -= fill_tileX(avctx, 1024, 1024, fill, frame);
164         if (resolution_flag & 0x08)
165             prev_pixels -= fill_tileX(avctx, 256, 256, fill, frame);
166         if (resolution_flag & 0x04)
167             prev_pixels -= fill_tileX(avctx, 64, 64, fill, frame);
168         if (resolution_flag & 0x02)
169             prev_pixels -= fill_tileX(avctx, 16, 16, fill, frame);
170         if (resolution_flag & 0x01)
171             prev_pixels -= fill_tile4(avctx, fill, frame);
172     }
173 
174     av_frame_unref(s->prev_frame);
175     if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
176         return ret;
177 
178     frame->pict_type = prev_pixels <= 0 ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
179     frame->key_frame = prev_pixels <= 0;
180     *got_frame = 1;
181 
182     return avpkt->size;
183 }
184 
decode_init(AVCodecContext * avctx)185 static av_cold int decode_init(AVCodecContext *avctx)
186 {
187     ARBCContext *s = avctx->priv_data;
188 
189     avctx->pix_fmt = AV_PIX_FMT_RGB24;
190 
191     s->prev_frame = av_frame_alloc();
192     if (!s->prev_frame)
193         return AVERROR(ENOMEM);
194 
195     return 0;
196 }
197 
decode_flush(AVCodecContext * avctx)198 static void decode_flush(AVCodecContext *avctx)
199 {
200     ARBCContext *s = avctx->priv_data;
201 
202     av_frame_unref(s->prev_frame);
203 }
204 
decode_close(AVCodecContext * avctx)205 static av_cold int decode_close(AVCodecContext *avctx)
206 {
207     ARBCContext *s = avctx->priv_data;
208 
209     av_frame_free(&s->prev_frame);
210 
211     return 0;
212 }
213 
214 const FFCodec ff_arbc_decoder = {
215     .p.name         = "arbc",
216     .p.long_name    = NULL_IF_CONFIG_SMALL("Gryphon's Anim Compressor"),
217     .p.type         = AVMEDIA_TYPE_VIDEO,
218     .p.id           = AV_CODEC_ID_ARBC,
219     .priv_data_size = sizeof(ARBCContext),
220     .init           = decode_init,
221     FF_CODEC_DECODE_CB(decode_frame),
222     .flush          = decode_flush,
223     .close          = decode_close,
224     .p.capabilities = AV_CODEC_CAP_DR1,
225     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
226 };
227