FFmpeg  4.0
y41pdec.c
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1 /*
2  * y41p decoder
3  *
4  * Copyright (c) 2012 Paul B Mahol
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_YUV411P;
29  avctx->bits_per_raw_sample = 12;
30 
31  if (avctx->width & 7) {
32  av_log(avctx, AV_LOG_WARNING, "y41p requires width to be divisible by 8.\n");
33  }
34 
35  return 0;
36 }
37 
38 static int y41p_decode_frame(AVCodecContext *avctx, void *data,
39  int *got_frame, AVPacket *avpkt)
40 {
41  AVFrame *pic = data;
42  uint8_t *src = avpkt->data;
43  uint8_t *y, *u, *v;
44  int i, j, ret;
45 
46  if (avpkt->size < 3LL * avctx->height * FFALIGN(avctx->width, 8) / 2) {
47  av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
48  return AVERROR(EINVAL);
49  }
50 
51  if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
52  return ret;
53 
54  pic->key_frame = 1;
56 
57  for (i = avctx->height - 1; i >= 0 ; i--) {
58  y = &pic->data[0][i * pic->linesize[0]];
59  u = &pic->data[1][i * pic->linesize[1]];
60  v = &pic->data[2][i * pic->linesize[2]];
61  for (j = 0; j < avctx->width; j += 8) {
62  *(u++) = *src++;
63  *(y++) = *src++;
64  *(v++) = *src++;
65  *(y++) = *src++;
66 
67  *(u++) = *src++;
68  *(y++) = *src++;
69  *(v++) = *src++;
70  *(y++) = *src++;
71 
72  *(y++) = *src++;
73  *(y++) = *src++;
74  *(y++) = *src++;
75  *(y++) = *src++;
76  }
77  }
78 
79  *got_frame = 1;
80 
81  return avpkt->size;
82 }
83 
85  .name = "y41p",
86  .long_name = NULL_IF_CONFIG_SMALL("Uncompressed YUV 4:1:1 12-bit"),
87  .type = AVMEDIA_TYPE_VIDEO,
88  .id = AV_CODEC_ID_Y41P,
89  .init = y41p_decode_init,
90  .decode = y41p_decode_frame,
91  .capabilities = AV_CODEC_CAP_DR1,
92 };
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int size
Definition: avcodec.h:1431
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1727
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:2741
#define src
Definition: vp8dsp.c:254
static int y41p_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: y41pdec.c:38
AVCodec.
Definition: avcodec.h:3408
uint8_t
#define av_cold
Definition: attributes.h:82
#define u(width, name, range_min, range_max)
Definition: cbs_h2645.c:344
const char data[16]
Definition: mxf.c:90
uint8_t * data
Definition: avcodec.h:1430
#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 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:186
AVCodec ff_y41p_decoder
Definition: y41pdec.c:84
const char * name
Name of the codec implementation.
Definition: avcodec.h:3415
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:301
int width
picture width / height.
Definition: avcodec.h:1690
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:249
main external API structure.
Definition: avcodec.h:1518
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1891
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
common internal api header.
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:69
static av_cold int y41p_decode_init(AVCodecContext *avctx)
Definition: y41pdec.c:26
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:296
This structure stores compressed data.
Definition: avcodec.h:1407
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:959