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yuv4dec.c
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1 /*
2  * libquicktime yuv4 decoder
3  *
4  * Copyright (c) 2011 Carl Eugen Hoyos
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "avcodec.h"
24 #include "internal.h"
25 
27 {
28  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
29 
30  return 0;
31 }
32 
33 static int yuv4_decode_frame(AVCodecContext *avctx, void *data,
34  int *got_frame, AVPacket *avpkt)
35 {
36  AVFrame *pic = data;
37  const uint8_t *src = avpkt->data;
38  uint8_t *y, *u, *v;
39  int i, j, ret;
40 
41  if (avpkt->size < 6 * (avctx->width + 1 >> 1) * (avctx->height + 1 >> 1)) {
42  av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
43  return AVERROR(EINVAL);
44  }
45 
46  if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
47  return ret;
48 
49  pic->key_frame = 1;
51 
52  y = pic->data[0];
53  u = pic->data[1];
54  v = pic->data[2];
55 
56  for (i = 0; i < (avctx->height + 1) >> 1; i++) {
57  for (j = 0; j < (avctx->width + 1) >> 1; j++) {
58  u[j] = *src++ ^ 0x80;
59  v[j] = *src++ ^ 0x80;
60  y[ 2 * j ] = *src++;
61  y[ 2 * j + 1] = *src++;
62  y[pic->linesize[0] + 2 * j ] = *src++;
63  y[pic->linesize[0] + 2 * j + 1] = *src++;
64  }
65 
66  y += 2 * pic->linesize[0];
67  u += pic->linesize[1];
68  v += pic->linesize[2];
69  }
70 
71  *got_frame = 1;
72 
73  return avpkt->size;
74 }
75 
77  .name = "yuv4",
78  .long_name = NULL_IF_CONFIG_SMALL("Uncompressed packed 4:2:0"),
79  .type = AVMEDIA_TYPE_VIDEO,
80  .id = AV_CODEC_ID_YUV4,
81  .init = yuv4_decode_init,
82  .decode = yuv4_decode_frame,
83  .capabilities = AV_CODEC_CAP_DR1,
84 };
This structure describes decoded (raw) audio or video data.
Definition: frame.h:180
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static int yuv4_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: yuv4dec.c:33
static av_cold int yuv4_decode_init(AVCodecContext *avctx)
Definition: yuv4dec.c:26
int size
Definition: avcodec.h:1578
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1870
AVCodec.
Definition: avcodec.h:3535
uint8_t
#define av_cold
Definition: attributes.h:82
uint8_t * data
Definition: avcodec.h:1577
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
const char * name
Name of the codec implementation.
Definition: avcodec.h:3542
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:254
int width
picture width / height.
Definition: avcodec.h:1829
#define src
Definition: vp9dsp.c:530
AVCodec ff_yuv4_decoder
Definition: yuv4dec.c:76
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:211
main external API structure.
Definition: avcodec.h:1642
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:928
#define u(width,...)
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:194
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:62
common internal api header.
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:249
This structure stores compressed data.
Definition: avcodec.h:1554
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:953