FFmpeg
ptx.c
Go to the documentation of this file.
1 /*
2  * V.Flash PTX (.ptx) image decoder
3  * Copyright (c) 2007 Ivo van Poorten
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 "libavutil/common.h"
23 #include "libavutil/intreadwrite.h"
24 #include "libavutil/imgutils.h"
25 #include "avcodec.h"
26 #include "internal.h"
27 
28 static int ptx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
29  AVPacket *avpkt) {
30  const uint8_t *buf = avpkt->data;
31  const uint8_t *buf_end = avpkt->data + avpkt->size;
32  AVFrame * const p = data;
33  unsigned int offset, w, h, y, stride, bytes_per_pixel;
34  int ret;
35  uint8_t *ptr;
36 
37  if (buf_end - buf < 14)
38  return AVERROR_INVALIDDATA;
39  offset = AV_RL16(buf);
40  w = AV_RL16(buf+8);
41  h = AV_RL16(buf+10);
42  bytes_per_pixel = AV_RL16(buf+12) >> 3;
43 
44  if (bytes_per_pixel != 2) {
45  avpriv_request_sample(avctx, "Image format not RGB15");
46  return AVERROR_PATCHWELCOME;
47  }
48 
50 
51  if (buf_end - buf < offset)
52  return AVERROR_INVALIDDATA;
53  if (offset != 0x2c)
54  avpriv_request_sample(avctx, "offset != 0x2c");
55 
56  buf += offset;
57 
58  if (buf_end - buf < w * bytes_per_pixel)
59  return AVERROR_INVALIDDATA;
60 
61  if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
62  return ret;
63 
64  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
65  return ret;
66 
68 
69  ptr = p->data[0];
70  stride = p->linesize[0];
71 
72  for (y = 0; y < h && buf_end - buf >= w * bytes_per_pixel; y++) {
73  memcpy(ptr, buf, w*bytes_per_pixel);
74  ptr += stride;
75  buf += w*bytes_per_pixel;
76  }
77 
78  *got_frame = 1;
79 
80  if (y < h) {
81  av_log(avctx, AV_LOG_WARNING, "incomplete packet\n");
82  return avpkt->size;
83  }
84 
85  return offset + w*h*bytes_per_pixel;
86 }
87 
89  .name = "ptx",
90  .long_name = NULL_IF_CONFIG_SMALL("V.Flash PTX image"),
91  .type = AVMEDIA_TYPE_VIDEO,
92  .id = AV_CODEC_ID_PTX,
93  .decode = ptx_decode_frame,
94  .capabilities = AV_CODEC_CAP_DR1,
95 };
AVCodec
AVCodec.
Definition: avcodec.h:3481
stride
int stride
Definition: mace.c:144
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
w
uint8_t w
Definition: llviddspenc.c:38
internal.h
AVPacket::data
uint8_t * data
Definition: avcodec.h:1477
data
const char data[16]
Definition: mxf.c:91
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
buf
void * buf
Definition: avisynth_c.h:766
intreadwrite.h
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:90
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
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:378
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1965
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981
AVPacket::size
int size
Definition: avcodec.h:1478
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
ptx_decode_frame
static int ptx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: ptx.c:28
common.h
uint8_t
uint8_t
Definition: audio_convert.c:194
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:1565
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
ff_set_dimensions
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:104
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:39
AV_PIX_FMT_BGR555LE
@ AV_PIX_FMT_BGR555LE
packed BGR 5:5:5, 16bpp, (msb)1X 5B 5G 5R(lsb), little-endian, X=unused/undefined
Definition: pixfmt.h:113
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1454
ff_ptx_decoder
AVCodec ff_ptx_decoder
Definition: ptx.c:88
imgutils.h
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
h
h
Definition: vp9dsp_template.c:2038
AV_CODEC_ID_PTX
@ AV_CODEC_ID_PTX
Definition: avcodec.h:322