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  for (i = avctx->height - 1; i >= 0 ; i--) {
55  y = &pic->data[0][i * pic->linesize[0]];
56  u = &pic->data[1][i * pic->linesize[1]];
57  v = &pic->data[2][i * pic->linesize[2]];
58  for (j = 0; j < avctx->width; j += 8) {
59  *(u++) = *src++;
60  *(y++) = *src++;
61  *(v++) = *src++;
62  *(y++) = *src++;
63 
64  *(u++) = *src++;
65  *(y++) = *src++;
66  *(v++) = *src++;
67  *(y++) = *src++;
68 
69  *(y++) = *src++;
70  *(y++) = *src++;
71  *(y++) = *src++;
72  *(y++) = *src++;
73  }
74  }
75 
76  *got_frame = 1;
77 
78  return avpkt->size;
79 }
80 
82  .p.name = "y41p",
83  CODEC_LONG_NAME("Uncompressed YUV 4:1:1 12-bit"),
84  .p.type = AVMEDIA_TYPE_VIDEO,
85  .p.id = AV_CODEC_ID_Y41P,
86  .init = y41p_decode_init,
88  .p.capabilities = AV_CODEC_CAP_DR1,
89 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:215
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:251
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:389
AVPacket::data
uint8_t * data
Definition: packet.h:539
FFCodec
Definition: codec_internal.h:127
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:410
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:209
av_cold
#define av_cold
Definition: attributes.h:90
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:311
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1585
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:296
ff_y41p_decoder
const FFCodec ff_y41p_decoder
Definition: y41pdec.c:81
AV_CODEC_ID_Y41P
@ AV_CODEC_ID_Y41P
Definition: codec_id.h:254
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1697
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:540
codec_internal.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
AVCodecContext::height
int height
Definition: avcodec.h:624
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:663
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:451
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:516
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:80
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:624
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:434
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
src
#define src
Definition: vp8dsp.c:248