FFmpeg
cyuv.c
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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 <string.h>
34 
35 #include "avcodec.h"
36 #include "codec_internal.h"
37 #include "decode.h"
38 #include "libavutil/internal.h"
39 
41 {
42  /* width needs to be divisible by 4 for this codec to work */
43  if (avctx->width & 0x3)
44  return AVERROR_INVALIDDATA;
45 
46  return 0;
47 }
48 
50  int *got_frame, AVPacket *avpkt)
51 {
52  const uint8_t *buf = avpkt->data;
53  int buf_size = avpkt->size;
54 
55  unsigned char *y_plane;
56  unsigned char *u_plane;
57  unsigned char *v_plane;
58  int y_ptr;
59  int u_ptr;
60  int v_ptr;
61 
62  /* prediction error tables (make it clear that they are signed values) */
63  const signed char *y_table = (const signed char*)buf + 0;
64  const signed char *u_table = (const signed char*)buf + 16;
65  const signed char *v_table = (const signed char*)buf + 32;
66 
67  unsigned char y_pred, u_pred, v_pred;
68  int stream_ptr;
69  unsigned char cur_byte;
70  int pixel_groups;
71  int rawsize = avctx->height * FFALIGN(avctx->width,2) * 2;
72  int ret;
73 
74  if (avctx->codec_id == AV_CODEC_ID_AURA) {
75  y_table = u_table;
76  u_table = v_table;
77  }
78  /* sanity check the buffer size: A buffer has 3x16-bytes tables
79  * followed by (height) lines each with 3 bytes to represent groups
80  * of 4 pixels. Thus, the total size of the buffer ought to be:
81  * (3 * 16) + height * (width * 3 / 4) */
82  if (buf_size == 48 + avctx->height * (avctx->width * 3 / 4)) {
83  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
84  } else if(buf_size == rawsize ) {
85  avctx->pix_fmt = AV_PIX_FMT_UYVY422;
86  } else {
87  av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n",
88  buf_size, 48 + avctx->height * (avctx->width * 3 / 4));
89  return AVERROR_INVALIDDATA;
90  }
91 
92  /* pixel data starts 48 bytes in, after 3x16-byte tables */
93  stream_ptr = 48;
94 
95  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
96  return ret;
97 
98  y_plane = frame->data[0];
99  u_plane = frame->data[1];
100  v_plane = frame->data[2];
101 
102  if (buf_size == rawsize) {
103  int linesize = FFALIGN(avctx->width, 2) * 2;
104  y_plane += frame->linesize[0] * avctx->height;
105  for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) {
106  y_plane -= frame->linesize[0];
107  memcpy(y_plane, buf+stream_ptr, linesize);
108  }
109  } else {
110 
111  /* iterate through each line in the height */
112  for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
113  y_ptr < (avctx->height * frame->linesize[0]);
114  y_ptr += frame->linesize[0] - avctx->width,
115  u_ptr += frame->linesize[1] - avctx->width / 4,
116  v_ptr += frame->linesize[2] - avctx->width / 4) {
117 
118  /* reset predictors */
119  cur_byte = buf[stream_ptr++];
120  u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
121  y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;
122 
123  cur_byte = buf[stream_ptr++];
124  v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
125  y_pred += y_table[cur_byte & 0x0F];
126  y_plane[y_ptr++] = y_pred;
127 
128  cur_byte = buf[stream_ptr++];
129  y_pred += y_table[cur_byte & 0x0F];
130  y_plane[y_ptr++] = y_pred;
131  y_pred += y_table[(cur_byte & 0xF0) >> 4];
132  y_plane[y_ptr++] = y_pred;
133 
134  /* iterate through the remaining pixel groups (4 pixels/group) */
135  pixel_groups = avctx->width / 4 - 1;
136  while (pixel_groups--) {
137 
138  cur_byte = buf[stream_ptr++];
139  u_pred += u_table[(cur_byte & 0xF0) >> 4];
140  u_plane[u_ptr++] = u_pred;
141  y_pred += y_table[cur_byte & 0x0F];
142  y_plane[y_ptr++] = y_pred;
143 
144  cur_byte = buf[stream_ptr++];
145  v_pred += v_table[(cur_byte & 0xF0) >> 4];
146  v_plane[v_ptr++] = v_pred;
147  y_pred += y_table[cur_byte & 0x0F];
148  y_plane[y_ptr++] = y_pred;
149 
150  cur_byte = buf[stream_ptr++];
151  y_pred += y_table[cur_byte & 0x0F];
152  y_plane[y_ptr++] = y_pred;
153  y_pred += y_table[(cur_byte & 0xF0) >> 4];
154  y_plane[y_ptr++] = y_pred;
155 
156  }
157  }
158  }
159 
160  *got_frame = 1;
161 
162  return buf_size;
163 }
164 
165 #if CONFIG_AURA_DECODER
166 const FFCodec ff_aura_decoder = {
167  .p.name = "aura",
168  CODEC_LONG_NAME("Auravision AURA"),
169  .p.type = AVMEDIA_TYPE_VIDEO,
170  .p.id = AV_CODEC_ID_AURA,
171  .init = cyuv_decode_init,
173  .p.capabilities = AV_CODEC_CAP_DR1,
174 };
175 #endif
176 
177 #if CONFIG_CYUV_DECODER
178 const FFCodec ff_cyuv_decoder = {
179  .p.name = "cyuv",
180  CODEC_LONG_NAME("Creative YUV (CYUV)"),
181  .p.type = AVMEDIA_TYPE_VIDEO,
182  .p.id = AV_CODEC_ID_CYUV,
183  .init = cyuv_decode_init,
185  .p.capabilities = AV_CODEC_CAP_DR1,
186 };
187 #endif
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:491
FFCodec
Definition: codec_internal.h:127
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
cyuv_decode_frame
static int cyuv_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)
Definition: cyuv.c:49
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
cyuv_decode_init
static av_cold int cyuv_decode_init(AVCodecContext *avctx)
Definition: cyuv.c:40
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:451
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1617
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:492
codec_internal.h
ff_cyuv_decoder
const FFCodec ff_cyuv_decoder
AV_CODEC_ID_CYUV
@ AV_CODEC_ID_CYUV
Definition: codec_id.h:78
internal.h
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
AVCodecContext::height
int height
Definition: avcodec.h:621
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:658
ff_aura_decoder
const FFCodec ff_aura_decoder
avcodec.h
ret
ret
Definition: filter_design.txt:187
AV_PIX_FMT_UYVY422
@ AV_PIX_FMT_UYVY422
packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1
Definition: pixfmt.h:81
AVCodecContext
main external API structure.
Definition: avcodec.h:441
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:78
AVPacket
This structure stores compressed data.
Definition: packet.h:468
AV_PIX_FMT_YUV411P
@ AV_PIX_FMT_YUV411P
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:73
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:621
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:385
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AV_CODEC_ID_AURA
@ AV_CODEC_ID_AURA
Definition: codec_id.h:175