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 "codec_internal.h"
25 #include "decode.h"
26 
28 {
29  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
30  avctx->bits_per_raw_sample = 12;
31 
32  if (avctx->width & 7) {
33  av_log(avctx, AV_LOG_WARNING, "y41p requires width to be divisible by 8.\n");
34  }
35 
36  return 0;
37 }
38 
39 static int y41p_decode_frame(AVCodecContext *avctx, AVFrame *pic,
40  int *got_frame, AVPacket *avpkt)
41 {
42  const 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  .p.name = "y41p",
86  CODEC_LONG_NAME("Uncompressed YUV 4:1:1 12-bit"),
87  .p.type = AVMEDIA_TYPE_VIDEO,
88  .p.id = AV_CODEC_ID_Y41P,
89  .init = y41p_decode_init,
91  .p.capabilities = AV_CODEC_CAP_DR1,
92 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVERROR
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
u
#define u(width, name, range_min, range_max)
Definition: cbs_h2645.c:262
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
AVPacket::data
uint8_t * data
Definition: packet.h:374
FFCodec
Definition: codec_internal.h:119
y41p_decode_frame
static int y41p_decode_frame(AVCodecContext *avctx, AVFrame *pic, int *got_frame, AVPacket *avpkt)
Definition: y41pdec.c:39
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:346
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:123
AVFrame::key_frame
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:417
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
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:298
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1451
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:264
ff_y41p_decoder
const FFCodec ff_y41p_decoder
Definition: y41pdec.c:84
AV_CODEC_ID_Y41P
@ AV_CODEC_ID_Y41P
Definition: codec_id.h:252
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:422
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1450
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
codec_internal.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:211
AVCodecContext::height
int height
Definition: avcodec.h:571
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:608
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:398
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
y41p_decode_init
static av_cold int y41p_decode_init(AVCodecContext *avctx)
Definition: y41pdec.c:27
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:78
AVPacket
This structure stores compressed data.
Definition: packet.h:351
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
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:571
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:370
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27