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 <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 
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 
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
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:374
FFCodec
Definition: codec_internal.h:112
init
static int init
Definition: av_tx.c:47
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:116
CyuvDecodeContext
Definition: cyuv.c:43
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:62
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:254
s
#define s(width, name)
Definition: cbs_vp9.c:256
CyuvDecodeContext::width
int width
Definition: cyuv.c:45
cyuv_decode_init
static av_cold int cyuv_decode_init(AVCodecContext *avctx)
Definition: cyuv.c:48
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:399
CyuvDecodeContext::avctx
AVCodecContext * avctx
Definition: cyuv.c:44
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1403
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:375
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:116
codec_internal.h
ff_cyuv_decoder
const FFCodec ff_cyuv_decoder
AV_CODEC_ID_CYUV
@ AV_CODEC_ID_CYUV
Definition: codec_id.h:76
internal.h
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: codec_internal.h:31
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:203
AVCodecContext::height
int height
Definition: avcodec.h:562
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:599
ff_aura_decoder
const FFCodec ff_aura_decoder
avcodec.h
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
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:389
CyuvDecodeContext::height
int height
Definition: cyuv.c:45
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:351
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:416
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:562
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:173
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