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
7 * Copyright (C) 2003 the ffmpeg project
9 * This file is part of FFmpeg.
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.
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.
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
28 * Creative YUV (CYUV) Video Decoder.
37 #include "libavutil/internal.h"
40 typedef struct CyuvDecodeContext {
41 AVCodecContext *avctx;
46 static av_cold int cyuv_decode_init(AVCodecContext *avctx)
48 CyuvDecodeContext *s = avctx->priv_data;
51 s->width = avctx->width;
52 /* width needs to be divisible by 4 for this codec to work */
55 s->height = avctx->height;
56 avcodec_get_frame_defaults(&s->frame);
61 static int cyuv_decode_frame(AVCodecContext *avctx,
62 void *data, int *data_size,
65 const uint8_t *buf = avpkt->data;
66 int buf_size = avpkt->size;
67 CyuvDecodeContext *s=avctx->priv_data;
69 unsigned char *y_plane;
70 unsigned char *u_plane;
71 unsigned char *v_plane;
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;
81 unsigned char y_pred, u_pred, v_pred;
83 unsigned char cur_byte;
85 int rawsize = s->height * FFALIGN(s->width,2) * 2;
87 if (avctx->codec_id == AV_CODEC_ID_AURA) {
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 = PIX_FMT_YUV411P;
97 } else if(buf_size == rawsize ) {
98 avctx->pix_fmt = PIX_FMT_UYVY422;
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));
105 /* pixel data starts 48 bytes in, after 3x16-byte tables */
108 if (s->frame.data[0])
109 avctx->release_buffer(avctx, &s->frame);
111 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID;
112 s->frame.reference = 0;
113 if (avctx->get_buffer(avctx, &s->frame) < 0) {
114 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
118 y_plane = s->frame.data[0];
119 u_plane = s->frame.data[1];
120 v_plane = s->frame.data[2];
122 if (buf_size == rawsize) {
123 int linesize = FFALIGN(s->width,2) * 2;
124 y_plane += s->frame.linesize[0] * s->height;
125 for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) {
126 y_plane -= s->frame.linesize[0];
127 memcpy(y_plane, buf+stream_ptr, linesize);
131 /* iterate through each line in the height */
132 for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
133 y_ptr < (s->height * s->frame.linesize[0]);
134 y_ptr += s->frame.linesize[0] - s->width,
135 u_ptr += s->frame.linesize[1] - s->width / 4,
136 v_ptr += s->frame.linesize[2] - s->width / 4) {
138 /* reset predictors */
139 cur_byte = buf[stream_ptr++];
140 u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
141 y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;
143 cur_byte = buf[stream_ptr++];
144 v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
145 y_pred += y_table[cur_byte & 0x0F];
146 y_plane[y_ptr++] = y_pred;
148 cur_byte = buf[stream_ptr++];
149 y_pred += y_table[cur_byte & 0x0F];
150 y_plane[y_ptr++] = y_pred;
151 y_pred += y_table[(cur_byte & 0xF0) >> 4];
152 y_plane[y_ptr++] = y_pred;
154 /* iterate through the remaining pixel groups (4 pixels/group) */
155 pixel_groups = s->width / 4 - 1;
156 while (pixel_groups--) {
158 cur_byte = buf[stream_ptr++];
159 u_pred += u_table[(cur_byte & 0xF0) >> 4];
160 u_plane[u_ptr++] = u_pred;
161 y_pred += y_table[cur_byte & 0x0F];
162 y_plane[y_ptr++] = y_pred;
164 cur_byte = buf[stream_ptr++];
165 v_pred += v_table[(cur_byte & 0xF0) >> 4];
166 v_plane[v_ptr++] = v_pred;
167 y_pred += y_table[cur_byte & 0x0F];
168 y_plane[y_ptr++] = y_pred;
170 cur_byte = buf[stream_ptr++];
171 y_pred += y_table[cur_byte & 0x0F];
172 y_plane[y_ptr++] = y_pred;
173 y_pred += y_table[(cur_byte & 0xF0) >> 4];
174 y_plane[y_ptr++] = y_pred;
180 *data_size=sizeof(AVFrame);
181 *(AVFrame*)data= s->frame;
186 static av_cold int cyuv_decode_end(AVCodecContext *avctx)
188 CyuvDecodeContext *s = avctx->priv_data;
190 if (s->frame.data[0])
191 avctx->release_buffer(avctx, &s->frame);
196 #if CONFIG_AURA_DECODER
197 AVCodec ff_aura_decoder = {
199 .type = AVMEDIA_TYPE_VIDEO,
200 .id = AV_CODEC_ID_AURA,
201 .priv_data_size = sizeof(CyuvDecodeContext),
202 .init = cyuv_decode_init,
203 .close = cyuv_decode_end,
204 .decode = cyuv_decode_frame,
205 .capabilities = CODEC_CAP_DR1,
206 .long_name = NULL_IF_CONFIG_SMALL("Auravision AURA"),
210 #if CONFIG_CYUV_DECODER
211 AVCodec ff_cyuv_decoder = {
213 .type = AVMEDIA_TYPE_VIDEO,
214 .id = AV_CODEC_ID_CYUV,
215 .priv_data_size = sizeof(CyuvDecodeContext),
216 .init = cyuv_decode_init,
217 .close = cyuv_decode_end,
218 .decode = cyuv_decode_frame,
219 .capabilities = CODEC_CAP_DR1,
220 .long_name = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"),