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 "config_components.h"
32
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36
37 #include "avcodec.h"
38 #include "codec_internal.h"
39 #include "internal.h"
40 #include "libavutil/internal.h"
41
42
43 typedef struct CyuvDecodeContext {
44 AVCodecContext *avctx;
45 int width, height;
46 } CyuvDecodeContext;
47
cyuv_decode_init(AVCodecContext * avctx)48 static av_cold int cyuv_decode_init(AVCodecContext *avctx)
49 {
50 CyuvDecodeContext *s = avctx->priv_data;
51
52 s->avctx = avctx;
53 s->width = avctx->width;
54 /* width needs to be divisible by 4 for this codec to work */
55 if (s->width & 0x3)
56 return AVERROR_INVALIDDATA;
57 s->height = avctx->height;
58
59 return 0;
60 }
61
cyuv_decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame,AVPacket * avpkt)62 static int cyuv_decode_frame(AVCodecContext *avctx, AVFrame *frame,
63 int *got_frame, AVPacket *avpkt)
64 {
65 const uint8_t *buf = avpkt->data;
66 int buf_size = avpkt->size;
67 CyuvDecodeContext *s=avctx->priv_data;
68
69 unsigned char *y_plane;
70 unsigned char *u_plane;
71 unsigned char *v_plane;
72 int y_ptr;
73 int u_ptr;
74 int v_ptr;
75
76 /* prediction error tables (make it clear that they are signed values) */
77 const signed char *y_table = (const signed char*)buf + 0;
78 const signed char *u_table = (const signed char*)buf + 16;
79 const signed char *v_table = (const signed char*)buf + 32;
80
81 unsigned char y_pred, u_pred, v_pred;
82 int stream_ptr;
83 unsigned char cur_byte;
84 int pixel_groups;
85 int rawsize = s->height * FFALIGN(s->width,2) * 2;
86 int ret;
87
88 if (avctx->codec_id == AV_CODEC_ID_AURA) {
89 y_table = u_table;
90 u_table = v_table;
91 }
92 /* sanity check the buffer size: A buffer has 3x16-bytes tables
93 * followed by (height) lines each with 3 bytes to represent groups
94 * of 4 pixels. Thus, the total size of the buffer ought to be:
95 * (3 * 16) + height * (width * 3 / 4) */
96 if (buf_size == 48 + s->height * (s->width * 3 / 4)) {
97 avctx->pix_fmt = AV_PIX_FMT_YUV411P;
98 } else if(buf_size == rawsize ) {
99 avctx->pix_fmt = AV_PIX_FMT_UYVY422;
100 } else {
101 av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n",
102 buf_size, 48 + s->height * (s->width * 3 / 4));
103 return AVERROR_INVALIDDATA;
104 }
105
106 /* pixel data starts 48 bytes in, after 3x16-byte tables */
107 stream_ptr = 48;
108
109 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
110 return ret;
111
112 y_plane = frame->data[0];
113 u_plane = frame->data[1];
114 v_plane = frame->data[2];
115
116 if (buf_size == rawsize) {
117 int linesize = FFALIGN(s->width,2) * 2;
118 y_plane += frame->linesize[0] * s->height;
119 for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) {
120 y_plane -= frame->linesize[0];
121 memcpy(y_plane, buf+stream_ptr, linesize);
122 }
123 } else {
124
125 /* iterate through each line in the height */
126 for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
127 y_ptr < (s->height * frame->linesize[0]);
128 y_ptr += frame->linesize[0] - s->width,
129 u_ptr += frame->linesize[1] - s->width / 4,
130 v_ptr += frame->linesize[2] - s->width / 4) {
131
132 /* reset predictors */
133 cur_byte = buf[stream_ptr++];
134 u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
135 y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;
136
137 cur_byte = buf[stream_ptr++];
138 v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
139 y_pred += y_table[cur_byte & 0x0F];
140 y_plane[y_ptr++] = y_pred;
141
142 cur_byte = buf[stream_ptr++];
143 y_pred += y_table[cur_byte & 0x0F];
144 y_plane[y_ptr++] = y_pred;
145 y_pred += y_table[(cur_byte & 0xF0) >> 4];
146 y_plane[y_ptr++] = y_pred;
147
148 /* iterate through the remaining pixel groups (4 pixels/group) */
149 pixel_groups = s->width / 4 - 1;
150 while (pixel_groups--) {
151
152 cur_byte = buf[stream_ptr++];
153 u_pred += u_table[(cur_byte & 0xF0) >> 4];
154 u_plane[u_ptr++] = u_pred;
155 y_pred += y_table[cur_byte & 0x0F];
156 y_plane[y_ptr++] = y_pred;
157
158 cur_byte = buf[stream_ptr++];
159 v_pred += v_table[(cur_byte & 0xF0) >> 4];
160 v_plane[v_ptr++] = v_pred;
161 y_pred += y_table[cur_byte & 0x0F];
162 y_plane[y_ptr++] = y_pred;
163
164 cur_byte = buf[stream_ptr++];
165 y_pred += y_table[cur_byte & 0x0F];
166 y_plane[y_ptr++] = y_pred;
167 y_pred += y_table[(cur_byte & 0xF0) >> 4];
168 y_plane[y_ptr++] = y_pred;
169
170 }
171 }
172 }
173
174 *got_frame = 1;
175
176 return buf_size;
177 }
178
179 #if CONFIG_AURA_DECODER
180 const FFCodec ff_aura_decoder = {
181 .p.name = "aura",
182 .p.long_name = NULL_IF_CONFIG_SMALL("Auravision AURA"),
183 .p.type = AVMEDIA_TYPE_VIDEO,
184 .p.id = AV_CODEC_ID_AURA,
185 .priv_data_size = sizeof(CyuvDecodeContext),
186 .init = cyuv_decode_init,
187 FF_CODEC_DECODE_CB(cyuv_decode_frame),
188 .p.capabilities = AV_CODEC_CAP_DR1,
189 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
190 };
191 #endif
192
193 #if CONFIG_CYUV_DECODER
194 const FFCodec ff_cyuv_decoder = {
195 .p.name = "cyuv",
196 .p.long_name = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"),
197 .p.type = AVMEDIA_TYPE_VIDEO,
198 .p.id = AV_CODEC_ID_CYUV,
199 .priv_data_size = sizeof(CyuvDecodeContext),
200 .init = cyuv_decode_init,
201 FF_CODEC_DECODE_CB(cyuv_decode_frame),
202 .p.capabilities = AV_CODEC_CAP_DR1,
203 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
204 };
205 #endif
206