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sgirledec.c
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1 /*
2  * Silicon Graphics RLE 8-bit video decoder
3  * Copyright (c) 2012 Peter Ross
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 /**
23  * @file
24  * Silicon Graphics RLE 8-bit video decoder
25  * @note Data is packed in rbg323 with rle, contained in mv or mov.
26  * The algorithm and pixfmt are subtly different from SGI images.
27  */
28 
29 #include "libavutil/common.h"
30 
31 #include "avcodec.h"
32 #include "internal.h"
33 
35 {
36  avctx->pix_fmt = AV_PIX_FMT_BGR8;
37  return 0;
38 }
39 
40 /**
41  * Convert SGI RBG323 pixel into AV_PIX_FMT_BGR8
42  * SGI RGB data is packed as 8bpp, (msb)3R 2B 3G(lsb)
43  */
44 #define RBG323_TO_BGR8(x) ((((x) << 3) & 0xC0) | \
45  (((x) << 3) & 0x38) | \
46  (((x) >> 5) & 7))
47 static av_always_inline
48 void rbg323_to_bgr8(uint8_t *dst, const uint8_t *src, int size)
49 {
50  int i;
51  for (i = 0; i < size; i++)
52  dst[i] = RBG323_TO_BGR8(src[i]);
53 }
54 
55 /**
56  * @param[out] dst Destination buffer
57  * @param[in] src Source buffer
58  * @param src_size Source buffer size (bytes)
59  * @param width Width of destination buffer (pixels)
60  * @param height Height of destination buffer (pixels)
61  * @param linesize Line size of destination buffer (bytes)
62  *
63  * @return <0 on error
64  */
65 static int decode_sgirle8(AVCodecContext *avctx, uint8_t *dst,
66  const uint8_t *src, int src_size,
67  int width, int height, ptrdiff_t linesize)
68 {
69  const uint8_t *src_end = src + src_size;
70  int x = 0, y = 0;
71 
72 #define INC_XY(n) \
73  x += n; \
74  if (x >= width) { \
75  y++; \
76  if (y >= height) \
77  return 0; \
78  x = 0; \
79  }
80 
81  while (src_end - src >= 2) {
82  uint8_t v = *src++;
83  if (v > 0 && v < 0xC0) {
84  do {
85  int length = FFMIN(v, width - x);
86  if (length <= 0)
87  break;
88  memset(dst + y * linesize + x, RBG323_TO_BGR8(*src), length);
89  INC_XY(length);
90  v -= length;
91  } while (v > 0);
92  src++;
93  } else if (v >= 0xC1) {
94  v -= 0xC0;
95  do {
96  int length = FFMIN3(v, width - x, src_end - src);
97  if (src_end - src < length || length <= 0)
98  break;
99  rbg323_to_bgr8(dst + y * linesize + x, src, length);
100  INC_XY(length);
101  src += length;
102  v -= length;
103  } while (v > 0);
104  } else {
105  avpriv_request_sample(avctx, "opcode %d", v);
106  return AVERROR_PATCHWELCOME;
107  }
108  }
109  return 0;
110 }
111 
112 static int sgirle_decode_frame(AVCodecContext *avctx, void *data,
113  int *got_frame, AVPacket *avpkt)
114 {
115  AVFrame *frame = data;
116  int ret;
117 
118  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
119  return ret;
120 
121  ret = decode_sgirle8(avctx, frame->data[0], avpkt->data, avpkt->size,
122  avctx->width, avctx->height, frame->linesize[0]);
123  if (ret < 0)
124  return ret;
125 
126  frame->pict_type = AV_PICTURE_TYPE_I;
127  frame->key_frame = 1;
128 
129  *got_frame = 1;
130 
131  return avpkt->size;
132 }
133 
135  .name = "sgirle",
136  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics RLE 8-bit video"),
137  .type = AVMEDIA_TYPE_VIDEO,
138  .id = AV_CODEC_ID_SGIRLE,
139  .init = sgirle_decode_init,
140  .decode = sgirle_decode_frame,
141  .capabilities = AV_CODEC_CAP_DR1,
142 };
This structure describes decoded (raw) audio or video data.
Definition: frame.h:226
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
static int sgirle_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: sgirledec.c:112
int size
Definition: avcodec.h:1446
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1743
#define src
Definition: vp8dsp.c:254
AVCodec.
Definition: avcodec.h:3424
static int decode_sgirle8(AVCodecContext *avctx, uint8_t *dst, const uint8_t *src, int src_size, int width, int height, ptrdiff_t linesize)
Definition: sgirledec.c:65
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 av_cold
Definition: attributes.h:82
static av_always_inline void rbg323_to_bgr8(uint8_t *dst, const uint8_t *src, int size)
Definition: sgirledec.c:48
static AVFrame * frame
#define height
uint8_t * data
Definition: avcodec.h:1445
#define FFMIN3(a, b, c)
Definition: common.h:97
ptrdiff_t size
Definition: opengl_enc.c:101
#define RBG323_TO_BGR8(x)
Convert SGI RBG323 pixel into AV_PIX_FMT_BGR8 SGI RGB data is packed as 8bpp, (msb)3R 2B 3G(lsb) ...
Definition: sgirledec.c:44
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
GLsizei GLsizei * length
Definition: opengl_enc.c:115
const char * name
Name of the codec implementation.
Definition: avcodec.h:3431
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:309
#define FFMIN(a, b)
Definition: common.h:96
#define width
int width
picture width / height.
Definition: avcodec.h:1706
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
Definition: pixfmt.h:83
Libavcodec external API header.
static av_cold int sgirle_decode_init(AVCodecContext *avctx)
Definition: sgirledec.c:34
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:257
#define INC_XY(n)
main external API structure.
Definition: avcodec.h:1533
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1918
AVCodec ff_sgirle_decoder
Definition: sgirledec.c:134
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:240
common internal api header.
common internal and external API header
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:304
#define av_always_inline
Definition: attributes.h:39
This structure stores compressed data.
Definition: avcodec.h:1422
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:968