FFmpeg
avuidec.c
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1 /*
2  * AVID Meridien decoder
3  *
4  * Copyright (c) 2012 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 "codec_internal.h"
25 #include "decode.h"
26 #include "libavutil/intreadwrite.h"
27 
29 {
31  return 0;
32 }
33 
34 static int avui_decode_frame(AVCodecContext *avctx, AVFrame *pic,
35  int *got_frame, AVPacket *avpkt)
36 {
37  int ret;
38  const uint8_t *src = avpkt->data, *extradata = avctx->extradata;
39  const uint8_t *srca;
40  uint8_t *y, *u, *v, *a;
41  int transparent, interlaced = 1, skip, opaque_length, i, j, k;
42  uint32_t extradata_size = avctx->extradata_size;
43 
44  while (extradata_size >= 24) {
45  uint32_t atom_size = AV_RB32(extradata);
46  if (!memcmp(&extradata[4], "APRGAPRG0001", 12)) {
47  interlaced = extradata[19] != 1;
48  break;
49  }
50  if (atom_size && atom_size <= extradata_size) {
51  extradata += atom_size;
52  extradata_size -= atom_size;
53  } else {
54  break;
55  }
56  }
57  if (avctx->height == 486) {
58  skip = 10;
59  } else {
60  skip = 16;
61  }
62  opaque_length = 2 * avctx->width * (avctx->height + skip) + 4 * interlaced;
63  if (avpkt->size < opaque_length) {
64  av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
65  return AVERROR(EINVAL);
66  }
67  transparent = avctx->bits_per_coded_sample == 32 &&
68  avpkt->size >= opaque_length * 2 + 4;
69  srca = src + opaque_length + 5;
70 
71  if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
72  return ret;
73 
74  if (!interlaced) {
75  src += avctx->width * skip;
76  srca += avctx->width * skip;
77  }
78 
79  for (i = 0; i < interlaced + 1; i++) {
80  src += avctx->width * skip;
81  srca += avctx->width * skip;
82  if (interlaced && avctx->height == 486) {
83  y = pic->data[0] + (1 - i) * pic->linesize[0];
84  u = pic->data[1] + (1 - i) * pic->linesize[1];
85  v = pic->data[2] + (1 - i) * pic->linesize[2];
86  a = pic->data[3] + (1 - i) * pic->linesize[3];
87  } else {
88  y = pic->data[0] + i * pic->linesize[0];
89  u = pic->data[1] + i * pic->linesize[1];
90  v = pic->data[2] + i * pic->linesize[2];
91  a = pic->data[3] + i * pic->linesize[3];
92  }
93 
94  for (j = 0; j < avctx->height >> interlaced; j++) {
95  for (k = 0; k < avctx->width >> 1; k++) {
96  u[ k ] = *src++;
97  y[2 * k ] = *src++;
98  a[2 * k ] = 0xFF - (transparent ? *srca++ : 0);
99  srca++;
100  v[ k ] = *src++;
101  y[2 * k + 1] = *src++;
102  a[2 * k + 1] = 0xFF - (transparent ? *srca++ : 0);
103  srca++;
104  }
105 
106  y += (interlaced + 1) * pic->linesize[0];
107  u += (interlaced + 1) * pic->linesize[1];
108  v += (interlaced + 1) * pic->linesize[2];
109  a += (interlaced + 1) * pic->linesize[3];
110  }
111  src += 4;
112  srca += 4;
113  }
114  *got_frame = 1;
115 
116  return avpkt->size;
117 }
118 
120  .p.name = "avui",
121  CODEC_LONG_NAME("Avid Meridien Uncompressed"),
122  .p.type = AVMEDIA_TYPE_VIDEO,
123  .p.id = AV_CODEC_ID_AVUI,
124  .p.capabilities = AV_CODEC_CAP_DR1,
125  .init = avui_decode_init,
127 };
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
avui_decode_init
static av_cold int avui_decode_init(AVCodecContext *avctx)
Definition: avuidec.c:28
AVPacket::data
uint8_t * data
Definition: packet.h:539
FFCodec
Definition: codec_internal.h:127
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
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:530
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:311
intreadwrite.h
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:296
AV_CODEC_ID_AVUI
@ AV_CODEC_ID_AVUI
Definition: codec_id.h:255
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1692
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
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1578
interlaced
uint8_t interlaced
Definition: mxfenc.c:2265
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:529
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
ff_avui_decoder
const FFCodec ff_avui_decoder
Definition: avuidec.c:119
avui_decode_frame
static int avui_decode_frame(AVCodecContext *avctx, AVFrame *pic, int *got_frame, AVPacket *avpkt)
Definition: avuidec.c:34
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
AVPacket
This structure stores compressed data.
Definition: packet.h:516
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
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:375
src
#define src
Definition: vp8dsp.c:248
AV_PIX_FMT_YUVA422P
@ AV_PIX_FMT_YUVA422P
planar YUV 4:2:2 24bpp, (1 Cr & Cb sample per 2x1 Y & A samples)
Definition: pixfmt.h:173