FFmpeg
rawutils.c
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1 /*
2  * Raw video utils
3  * Copyright (c) 2016 Michael Niedermayer
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avformat.h"
23 #include "internal.h"
24 
25 int ff_reshuffle_raw_rgb(AVFormatContext *s, AVPacket **ppkt, AVCodecParameters *par, int expected_stride)
26 {
27  int ret;
28  AVPacket *pkt = *ppkt;
29  int64_t bpc = par->bits_per_coded_sample != 15 ? par->bits_per_coded_sample : 16;
30  int min_stride = (par->width * bpc + 7) >> 3;
31  int with_pal_size = min_stride * par->height + 1024;
32  int contains_pal = bpc == 8 && pkt->size == with_pal_size;
33  int size = contains_pal ? min_stride * par->height : pkt->size;
34  int stride = size / par->height;
35  int padding = expected_stride - FFMIN(expected_stride, stride);
36  int y;
37  AVPacket *new_pkt;
38 
39  if (pkt->size == expected_stride * par->height)
40  return 0;
41  if (size != stride * par->height)
42  return 0;
43 
44  new_pkt = av_packet_alloc();
45  if (!new_pkt)
46  return AVERROR(ENOMEM);
47 
48  ret = av_new_packet(new_pkt, expected_stride * par->height);
49  if (ret < 0)
50  goto fail;
51 
52  ret = av_packet_copy_props(new_pkt, pkt);
53  if (ret < 0)
54  goto fail;
55 
56  for (y = 0; y<par->height; y++) {
57  memcpy(new_pkt->data + y*expected_stride, pkt->data + y*stride, FFMIN(expected_stride, stride));
58  memset(new_pkt->data + y*expected_stride + expected_stride - padding, 0, padding);
59  }
60 
61  *ppkt = new_pkt;
62  return 1 + contains_pal;
63 fail:
64  av_packet_free(&new_pkt);
65 
66  return ret;
67 }
stride
int stride
Definition: mace.c:144
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
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
AVPacket::data
uint8_t * data
Definition: packet.h:373
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:75
fail
#define fail()
Definition: checkasm.h:127
pkt
AVPacket * pkt
Definition: movenc.c:59
s
#define s(width, name)
Definition: cbs_vp9.c:257
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:99
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
internal.h
AVPacket::size
int size
Definition: packet.h:374
size
int size
Definition: twinvq_data.h:10344
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:64
av_packet_copy_props
int av_packet_copy_props(AVPacket *dst, const AVPacket *src)
Copy only "properties" fields from src to dst.
Definition: avpacket.c:380
AVCodecParameters::height
int height
Definition: codec_par.h:127
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
ret
ret
Definition: filter_design.txt:187
avformat.h
ff_reshuffle_raw_rgb
int ff_reshuffle_raw_rgb(AVFormatContext *s, AVPacket **ppkt, AVCodecParameters *par, int expected_stride)
Reshuffles the lines to use the user specified stride.
Definition: rawutils.c:25
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
AVPacket
This structure stores compressed data.
Definition: packet.h:350