Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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 
49  avctx->pix_fmt = AV_PIX_FMT_RGB555;
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 ((ret = ff_set_dimensions(avctx, w, h)) < 0)
59  return ret;
60 
61  if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
62  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
63  return ret;
64  }
65 
67 
68  ptr = p->data[0];
69  stride = p->linesize[0];
70 
71  for (y = 0; y < h && buf_end - buf >= w * bytes_per_pixel; y++) {
72 #if HAVE_BIGENDIAN
73  unsigned int x;
74  for (x=0; x<w*bytes_per_pixel; x+=bytes_per_pixel)
75  AV_WN16(ptr+x, AV_RL16(buf+x));
76 #else
77  memcpy(ptr, buf, w*bytes_per_pixel);
78 #endif
79  ptr += stride;
80  buf += w*bytes_per_pixel;
81  }
82 
83  *got_frame = 1;
84 
85  if (y < h) {
86  av_log(avctx, AV_LOG_WARNING, "incomplete packet\n");
87  return avpkt->size;
88  }
89 
90  return offset + w*h*bytes_per_pixel;
91 }
92 
94  .name = "ptx",
95  .long_name = NULL_IF_CONFIG_SMALL("V.Flash PTX image"),
96  .type = AVMEDIA_TYPE_VIDEO,
97  .id = AV_CODEC_ID_PTX,
98  .decode = ptx_decode_frame,
99  .capabilities = CODEC_CAP_DR1,
100 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
AVCodec ff_ptx_decoder
Definition: ptx.c:93
misc image utilities
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
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:133
int size
Definition: avcodec.h:968
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1248
#define AV_RL16
Definition: intreadwrite.h:42
int stride
Definition: mace.c:144
AVCodec.
Definition: avcodec.h:2790
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:967
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:168
const char * name
Name of the codec implementation.
Definition: avcodec.h:2797
static int ptx_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: ptx.c:28
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:196
#define AVERROR_PATCHWELCOME
Not yet implemented in Libav, patches welcome.
Definition: error.h:57
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:153
main external API structure.
Definition: avcodec.h:1044
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:603
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
common internal api header.
common internal and external API header
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:231
#define AV_WN16(p, v)
Definition: intreadwrite.h:334
This structure stores compressed data.
Definition: avcodec.h:944