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 <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 
35 #include "avcodec.h"
36 #include "internal.h"
37 #include "libavutil/internal.h"
38 
39 
40 typedef struct CyuvDecodeContext {
42  int width, height;
44 
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 AVERROR_INVALIDDATA;
54  s->height = avctx->height;
55 
56  return 0;
57 }
58 
60  void *data, int *got_frame,
61  AVPacket *avpkt)
62 {
63  const uint8_t *buf = avpkt->data;
64  int buf_size = avpkt->size;
66  AVFrame *frame = 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  int rawsize = s->height * FFALIGN(s->width,2) * 2;
85  int ret;
86 
87  if (avctx->codec_id == AV_CODEC_ID_AURA) {
88  y_table = u_table;
89  u_table = v_table;
90  }
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 = AV_PIX_FMT_YUV411P;
97  } else if(buf_size == rawsize ) {
98  avctx->pix_fmt = AV_PIX_FMT_UYVY422;
99  } else {
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));
102  return AVERROR_INVALIDDATA;
103  }
104 
105  /* pixel data starts 48 bytes in, after 3x16-byte tables */
106  stream_ptr = 48;
107 
108  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
109  return ret;
110 
111  y_plane = frame->data[0];
112  u_plane = frame->data[1];
113  v_plane = frame->data[2];
114 
115  if (buf_size == rawsize) {
116  int linesize = FFALIGN(s->width,2) * 2;
117  y_plane += frame->linesize[0] * s->height;
118  for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) {
119  y_plane -= frame->linesize[0];
120  memcpy(y_plane, buf+stream_ptr, linesize);
121  }
122  } else {
123 
124  /* iterate through each line in the height */
125  for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
126  y_ptr < (s->height * frame->linesize[0]);
127  y_ptr += frame->linesize[0] - s->width,
128  u_ptr += frame->linesize[1] - s->width / 4,
129  v_ptr += frame->linesize[2] - s->width / 4) {
130 
131  /* reset predictors */
132  cur_byte = buf[stream_ptr++];
133  u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
134  y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;
135 
136  cur_byte = buf[stream_ptr++];
137  v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
138  y_pred += y_table[cur_byte & 0x0F];
139  y_plane[y_ptr++] = y_pred;
140 
141  cur_byte = buf[stream_ptr++];
142  y_pred += y_table[cur_byte & 0x0F];
143  y_plane[y_ptr++] = y_pred;
144  y_pred += y_table[(cur_byte & 0xF0) >> 4];
145  y_plane[y_ptr++] = y_pred;
146 
147  /* iterate through the remaining pixel groups (4 pixels/group) */
148  pixel_groups = s->width / 4 - 1;
149  while (pixel_groups--) {
150 
151  cur_byte = buf[stream_ptr++];
152  u_pred += u_table[(cur_byte & 0xF0) >> 4];
153  u_plane[u_ptr++] = u_pred;
154  y_pred += y_table[cur_byte & 0x0F];
155  y_plane[y_ptr++] = y_pred;
156 
157  cur_byte = buf[stream_ptr++];
158  v_pred += v_table[(cur_byte & 0xF0) >> 4];
159  v_plane[v_ptr++] = v_pred;
160  y_pred += y_table[cur_byte & 0x0F];
161  y_plane[y_ptr++] = y_pred;
162 
163  cur_byte = buf[stream_ptr++];
164  y_pred += y_table[cur_byte & 0x0F];
165  y_plane[y_ptr++] = y_pred;
166  y_pred += y_table[(cur_byte & 0xF0) >> 4];
167  y_plane[y_ptr++] = y_pred;
168 
169  }
170  }
171  }
172 
173  *got_frame = 1;
174 
175  return buf_size;
176 }
177 
178 #if CONFIG_AURA_DECODER
180  .name = "aura",
181  .long_name = NULL_IF_CONFIG_SMALL("Auravision AURA"),
182  .type = AVMEDIA_TYPE_VIDEO,
183  .id = AV_CODEC_ID_AURA,
184  .priv_data_size = sizeof(CyuvDecodeContext),
187  .capabilities = AV_CODEC_CAP_DR1,
188  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
189 };
190 #endif
191 
192 #if CONFIG_CYUV_DECODER
194  .name = "cyuv",
195  .long_name = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"),
196  .type = AVMEDIA_TYPE_VIDEO,
197  .id = AV_CODEC_ID_CYUV,
198  .priv_data_size = sizeof(CyuvDecodeContext),
201  .capabilities = AV_CODEC_CAP_DR1,
202  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
203 };
204 #endif
packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1
Definition: pixfmt.h:81
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:268
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1478
AVCodecContext * avctx
Definition: cyuv.c:41
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
AVCodec.
Definition: avcodec.h:3477
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
static av_cold int cyuv_decode_init(AVCodecContext *avctx)
Definition: cyuv.c:45
#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: internal.h:40
uint8_t
#define av_cold
Definition: attributes.h:82
uint8_t * data
Definition: avcodec.h:1477
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3484
common internal API header
int width
picture width / height.
Definition: avcodec.h:1738
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
#define s(width, name)
Definition: cbs_vp9.c:257
Libavcodec external API header.
enum AVCodecID codec_id
Definition: avcodec.h:1575
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:299
main external API structure.
Definition: avcodec.h:1565
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1964
void * buf
Definition: avisynth_c.h:766
AVCodec ff_cyuv_decoder
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
common internal api header.
static int cyuv_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: cyuv.c:59
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:73
void * priv_data
Definition: avcodec.h:1592
AVCodec ff_aura_decoder
This structure stores compressed data.
Definition: avcodec.h:1454
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981