cosmetics: Align codec declarations
[libav.git] / libavcodec / cyuv.c
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 Libav.
10 *
11 * Libav 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 * Libav 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 Libav; 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 "dsputil.h"
37
38
39 typedef struct CyuvDecodeContext {
40 AVCodecContext *avctx;
41 int width, height;
42 AVFrame frame;
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 -1;
54 s->height = avctx->height;
55 avctx->pix_fmt = PIX_FMT_YUV411P;
56
57 return 0;
58 }
59
60 static int cyuv_decode_frame(AVCodecContext *avctx,
61 void *data, int *data_size,
62 AVPacket *avpkt)
63 {
64 const uint8_t *buf = avpkt->data;
65 int buf_size = avpkt->size;
66 CyuvDecodeContext *s=avctx->priv_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
85 if (avctx->codec_id == CODEC_ID_AURA) {
86 y_table = u_table;
87 u_table = v_table;
88 }
89 /* sanity check the buffer size: A buffer has 3x16-bytes tables
90 * followed by (height) lines each with 3 bytes to represent groups
91 * of 4 pixels. Thus, the total size of the buffer ought to be:
92 * (3 * 16) + height * (width * 3 / 4) */
93 if (buf_size != 48 + s->height * (s->width * 3 / 4)) {
94 av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n",
95 buf_size, 48 + s->height * (s->width * 3 / 4));
96 return -1;
97 }
98
99 /* pixel data starts 48 bytes in, after 3x16-byte tables */
100 stream_ptr = 48;
101
102 if (s->frame.data[0])
103 avctx->release_buffer(avctx, &s->frame);
104
105 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID;
106 s->frame.reference = 0;
107 if (avctx->get_buffer(avctx, &s->frame) < 0) {
108 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
109 return -1;
110 }
111
112 y_plane = s->frame.data[0];
113 u_plane = s->frame.data[1];
114 v_plane = s->frame.data[2];
115
116 /* iterate through each line in the height */
117 for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
118 y_ptr < (s->height * s->frame.linesize[0]);
119 y_ptr += s->frame.linesize[0] - s->width,
120 u_ptr += s->frame.linesize[1] - s->width / 4,
121 v_ptr += s->frame.linesize[2] - s->width / 4) {
122
123 /* reset predictors */
124 cur_byte = buf[stream_ptr++];
125 u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
126 y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;
127
128 cur_byte = buf[stream_ptr++];
129 v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
130 y_pred += y_table[cur_byte & 0x0F];
131 y_plane[y_ptr++] = y_pred;
132
133 cur_byte = buf[stream_ptr++];
134 y_pred += y_table[cur_byte & 0x0F];
135 y_plane[y_ptr++] = y_pred;
136 y_pred += y_table[(cur_byte & 0xF0) >> 4];
137 y_plane[y_ptr++] = y_pred;
138
139 /* iterate through the remaining pixel groups (4 pixels/group) */
140 pixel_groups = s->width / 4 - 1;
141 while (pixel_groups--) {
142
143 cur_byte = buf[stream_ptr++];
144 u_pred += u_table[(cur_byte & 0xF0) >> 4];
145 u_plane[u_ptr++] = u_pred;
146 y_pred += y_table[cur_byte & 0x0F];
147 y_plane[y_ptr++] = y_pred;
148
149 cur_byte = buf[stream_ptr++];
150 v_pred += v_table[(cur_byte & 0xF0) >> 4];
151 v_plane[v_ptr++] = v_pred;
152 y_pred += y_table[cur_byte & 0x0F];
153 y_plane[y_ptr++] = y_pred;
154
155 cur_byte = buf[stream_ptr++];
156 y_pred += y_table[cur_byte & 0x0F];
157 y_plane[y_ptr++] = y_pred;
158 y_pred += y_table[(cur_byte & 0xF0) >> 4];
159 y_plane[y_ptr++] = y_pred;
160
161 }
162 }
163
164 *data_size=sizeof(AVFrame);
165 *(AVFrame*)data= s->frame;
166
167 return buf_size;
168 }
169
170 static av_cold int cyuv_decode_end(AVCodecContext *avctx)
171 {
172 CyuvDecodeContext *s = avctx->priv_data;
173
174 if (s->frame.data[0])
175 avctx->release_buffer(avctx, &s->frame);
176
177 return 0;
178 }
179
180 #if CONFIG_AURA_DECODER
181 AVCodec ff_aura_decoder = {
182 .name = "aura",
183 .type = AVMEDIA_TYPE_VIDEO,
184 .id = CODEC_ID_AURA,
185 .priv_data_size = sizeof(CyuvDecodeContext),
186 .init = cyuv_decode_init,
187 .close = cyuv_decode_end,
188 .decode = cyuv_decode_frame,
189 .capabilities = CODEC_CAP_DR1,
190 .long_name = NULL_IF_CONFIG_SMALL("Auravision AURA"),
191 };
192 #endif
193
194 #if CONFIG_CYUV_DECODER
195 AVCodec ff_cyuv_decoder = {
196 .name = "cyuv",
197 .type = AVMEDIA_TYPE_VIDEO,
198 .id = CODEC_ID_CYUV,
199 .priv_data_size = sizeof(CyuvDecodeContext),
200 .init = cyuv_decode_init,
201 .close = cyuv_decode_end,
202 .decode = cyuv_decode_frame,
203 .capabilities = CODEC_CAP_DR1,
204 .long_name = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"),
205 };
206 #endif