FFmpeg
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:268
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int size
Definition: avcodec.h:1478
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:2792
#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:3477
uint8_t
#define av_cold
Definition: attributes.h:82
#define u(width, name, range_min, range_max)
Definition: cbs_h2645.c:253
uint8_t * data
Definition: avcodec.h:1477
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:260
#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
AVCodec ff_y41p_decoder
Definition: y41pdec.c:84
const char * name
Name of the codec implementation.
Definition: avcodec.h:3484
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:351
int width
picture width / height.
Definition: avcodec.h:1738
Libavcodec external API header.
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
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
common internal api header.
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:73
static av_cold int y41p_decode_init(AVCodecContext *avctx)
Definition: y41pdec.c:26
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:346
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
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