blob: f2b0a7cbab7b87ed1ecbf9229656add6af65de43
1 | /* |
2 | * Creative YUV (CYUV) Video Decoder |
3 | * by Mike Melanson (melanson@pcisys.net) |
4 | * based on "Creative YUV (CYUV) stream format for AVI": |
5 | * http://www.csse.monash.edu.au/~timf/videocodec/cyuv.txt |
6 | * |
7 | * Copyright (C) 2003 The FFmpeg project |
8 | * |
9 | * This file is part of FFmpeg. |
10 | * |
11 | * FFmpeg is free software; you can redistribute it and/or |
12 | * modify it under the terms of the GNU Lesser General Public |
13 | * License as published by the Free Software Foundation; either |
14 | * version 2.1 of the License, or (at your option) any later version. |
15 | * |
16 | * FFmpeg is distributed in the hope that it will be useful, |
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
19 | * Lesser General Public License for more details. |
20 | * |
21 | * You should have received a copy of the GNU Lesser General Public |
22 | * License along with FFmpeg; if not, write to the Free Software |
23 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
24 | */ |
25 | |
26 | /** |
27 | * @file |
28 | * Creative YUV (CYUV) Video Decoder. |
29 | */ |
30 | |
31 | #include <stdio.h> |
32 | #include <stdlib.h> |
33 | #include <string.h> |
34 | |
35 | #include "avcodec.h" |
36 | #include "internal.h" |
37 | #include "libavutil/internal.h" |
38 | |
39 | |
40 | typedef struct CyuvDecodeContext { |
41 | AVCodecContext *avctx; |
42 | int width, height; |
43 | } CyuvDecodeContext; |
44 | |
45 | static av_cold int cyuv_decode_init(AVCodecContext *avctx) |
46 | { |
47 | CyuvDecodeContext *s = avctx->priv_data; |
48 | |
49 | s->avctx = avctx; |
50 | s->width = avctx->width; |
51 | /* width needs to be divisible by 4 for this codec to work */ |
52 | if (s->width & 0x3) |
53 | return AVERROR_INVALIDDATA; |
54 | s->height = avctx->height; |
55 | |
56 | return 0; |
57 | } |
58 | |
59 | static int cyuv_decode_frame(AVCodecContext *avctx, |
60 | void *data, int *got_frame, |
61 | AVPacket *avpkt) |
62 | { |
63 | const uint8_t *buf = avpkt->data; |
64 | int buf_size = avpkt->size; |
65 | CyuvDecodeContext *s=avctx->priv_data; |
66 | AVFrame *frame = data; |
67 | |
68 | unsigned char *y_plane; |
69 | unsigned char *u_plane; |
70 | unsigned char *v_plane; |
71 | int y_ptr; |
72 | int u_ptr; |
73 | int v_ptr; |
74 | |
75 | /* prediction error tables (make it clear that they are signed values) */ |
76 | const signed char *y_table = (const signed char*)buf + 0; |
77 | const signed char *u_table = (const signed char*)buf + 16; |
78 | const signed char *v_table = (const signed char*)buf + 32; |
79 | |
80 | unsigned char y_pred, u_pred, v_pred; |
81 | int stream_ptr; |
82 | unsigned char cur_byte; |
83 | int pixel_groups; |
84 | int rawsize = s->height * FFALIGN(s->width,2) * 2; |
85 | int ret; |
86 | |
87 | if (avctx->codec_id == AV_CODEC_ID_AURA) { |
88 | y_table = u_table; |
89 | u_table = v_table; |
90 | } |
91 | /* sanity check the buffer size: A buffer has 3x16-bytes tables |
92 | * followed by (height) lines each with 3 bytes to represent groups |
93 | * of 4 pixels. Thus, the total size of the buffer ought to be: |
94 | * (3 * 16) + height * (width * 3 / 4) */ |
95 | if (buf_size == 48 + s->height * (s->width * 3 / 4)) { |
96 | avctx->pix_fmt = AV_PIX_FMT_YUV411P; |
97 | } else if(buf_size == rawsize ) { |
98 | avctx->pix_fmt = AV_PIX_FMT_UYVY422; |
99 | } else { |
100 | av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n", |
101 | buf_size, 48 + s->height * (s->width * 3 / 4)); |
102 | return AVERROR_INVALIDDATA; |
103 | } |
104 | |
105 | /* pixel data starts 48 bytes in, after 3x16-byte tables */ |
106 | stream_ptr = 48; |
107 | |
108 | if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
109 | return ret; |
110 | |
111 | y_plane = frame->data[0]; |
112 | u_plane = frame->data[1]; |
113 | v_plane = frame->data[2]; |
114 | |
115 | if (buf_size == rawsize) { |
116 | int linesize = FFALIGN(s->width,2) * 2; |
117 | y_plane += frame->linesize[0] * s->height; |
118 | for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) { |
119 | y_plane -= frame->linesize[0]; |
120 | memcpy(y_plane, buf+stream_ptr, linesize); |
121 | } |
122 | } else { |
123 | |
124 | /* iterate through each line in the height */ |
125 | for (y_ptr = 0, u_ptr = 0, v_ptr = 0; |
126 | y_ptr < (s->height * frame->linesize[0]); |
127 | y_ptr += frame->linesize[0] - s->width, |
128 | u_ptr += frame->linesize[1] - s->width / 4, |
129 | v_ptr += frame->linesize[2] - s->width / 4) { |
130 | |
131 | /* reset predictors */ |
132 | cur_byte = buf[stream_ptr++]; |
133 | u_plane[u_ptr++] = u_pred = cur_byte & 0xF0; |
134 | y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4; |
135 | |
136 | cur_byte = buf[stream_ptr++]; |
137 | v_plane[v_ptr++] = v_pred = cur_byte & 0xF0; |
138 | y_pred += y_table[cur_byte & 0x0F]; |
139 | y_plane[y_ptr++] = y_pred; |
140 | |
141 | cur_byte = buf[stream_ptr++]; |
142 | y_pred += y_table[cur_byte & 0x0F]; |
143 | y_plane[y_ptr++] = y_pred; |
144 | y_pred += y_table[(cur_byte & 0xF0) >> 4]; |
145 | y_plane[y_ptr++] = y_pred; |
146 | |
147 | /* iterate through the remaining pixel groups (4 pixels/group) */ |
148 | pixel_groups = s->width / 4 - 1; |
149 | while (pixel_groups--) { |
150 | |
151 | cur_byte = buf[stream_ptr++]; |
152 | u_pred += u_table[(cur_byte & 0xF0) >> 4]; |
153 | u_plane[u_ptr++] = u_pred; |
154 | y_pred += y_table[cur_byte & 0x0F]; |
155 | y_plane[y_ptr++] = y_pred; |
156 | |
157 | cur_byte = buf[stream_ptr++]; |
158 | v_pred += v_table[(cur_byte & 0xF0) >> 4]; |
159 | v_plane[v_ptr++] = v_pred; |
160 | y_pred += y_table[cur_byte & 0x0F]; |
161 | y_plane[y_ptr++] = y_pred; |
162 | |
163 | cur_byte = buf[stream_ptr++]; |
164 | y_pred += y_table[cur_byte & 0x0F]; |
165 | y_plane[y_ptr++] = y_pred; |
166 | y_pred += y_table[(cur_byte & 0xF0) >> 4]; |
167 | y_plane[y_ptr++] = y_pred; |
168 | |
169 | } |
170 | } |
171 | } |
172 | |
173 | *got_frame = 1; |
174 | |
175 | return buf_size; |
176 | } |
177 | |
178 | #if CONFIG_AURA_DECODER |
179 | AVCodec ff_aura_decoder = { |
180 | .name = "aura", |
181 | .long_name = NULL_IF_CONFIG_SMALL("Auravision AURA"), |
182 | .type = AVMEDIA_TYPE_VIDEO, |
183 | .id = AV_CODEC_ID_AURA, |
184 | .priv_data_size = sizeof(CyuvDecodeContext), |
185 | .init = cyuv_decode_init, |
186 | .decode = cyuv_decode_frame, |
187 | .capabilities = AV_CODEC_CAP_DR1, |
188 | .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, |
189 | }; |
190 | #endif |
191 | |
192 | #if CONFIG_CYUV_DECODER |
193 | AVCodec ff_cyuv_decoder = { |
194 | .name = "cyuv", |
195 | .long_name = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"), |
196 | .type = AVMEDIA_TYPE_VIDEO, |
197 | .id = AV_CODEC_ID_CYUV, |
198 | .priv_data_size = sizeof(CyuvDecodeContext), |
199 | .init = cyuv_decode_init, |
200 | .decode = cyuv_decode_frame, |
201 | .capabilities = AV_CODEC_CAP_DR1, |
202 | .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, |
203 | }; |
204 | #endif |
205 |