FFmpeg
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 "codec_internal.h"
33 #include "decode.h"
34 
36 {
37  avctx->pix_fmt = AV_PIX_FMT_BGR8;
38  return 0;
39 }
40 
41 /**
42  * Convert SGI RBG323 pixel into AV_PIX_FMT_BGR8
43  * SGI RGB data is packed as 8bpp, (msb)3R 2B 3G(lsb)
44  */
45 #define RBG323_TO_BGR8(x) ((((x) << 3) & 0xC0) | \
46  (((x) << 3) & 0x38) | \
47  (((x) >> 5) & 7))
48 static av_always_inline
49 void rbg323_to_bgr8(uint8_t *dst, const uint8_t *src, int size)
50 {
51  int i;
52  for (i = 0; i < size; i++)
53  dst[i] = RBG323_TO_BGR8(src[i]);
54 }
55 
56 /**
57  * @param[out] dst Destination buffer
58  * @param[in] src Source buffer
59  * @param src_size Source buffer size (bytes)
60  * @param width Width of destination buffer (pixels)
61  * @param height Height of destination buffer (pixels)
62  * @param linesize Line size of destination buffer (bytes)
63  *
64  * @return <0 on error
65  */
66 static int decode_sgirle8(AVCodecContext *avctx, uint8_t *dst,
67  const uint8_t *src, int src_size,
68  int width, int height, ptrdiff_t linesize)
69 {
70  const uint8_t *src_end = src + src_size;
71  int x = 0, y = 0;
72 
73 #define INC_XY(n) \
74  x += n; \
75  if (x >= width) { \
76  y++; \
77  if (y >= height) \
78  return 0; \
79  x = 0; \
80  }
81 
82  while (src_end - src >= 2) {
83  uint8_t v = *src++;
84  if (v > 0 && v < 0xC0) {
85  do {
86  int length = FFMIN(v, width - x);
87  if (length <= 0)
88  break;
89  memset(dst + y * linesize + x, RBG323_TO_BGR8(*src), length);
90  INC_XY(length);
91  v -= length;
92  } while (v > 0);
93  src++;
94  } else if (v >= 0xC1) {
95  v -= 0xC0;
96  do {
97  int length = FFMIN3(v, width - x, src_end - src);
98  if (src_end - src < length || length <= 0)
99  break;
100  rbg323_to_bgr8(dst + y * linesize + x, src, length);
101  INC_XY(length);
102  src += length;
103  v -= length;
104  } while (v > 0);
105  } else {
106  avpriv_request_sample(avctx, "opcode %d", v);
107  return AVERROR_PATCHWELCOME;
108  }
109  }
110  return 0;
111 }
112 
114  int *got_frame, AVPacket *avpkt)
115 {
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 
128 
129  *got_frame = 1;
130 
131  return avpkt->size;
132 }
133 
135  .p.name = "sgirle",
136  CODEC_LONG_NAME("Silicon Graphics RLE 8-bit video"),
137  .p.type = AVMEDIA_TYPE_VIDEO,
138  .p.id = AV_CODEC_ID_SGIRLE,
139  .init = sgirle_decode_init,
141  .p.capabilities = AV_CODEC_CAP_DR1,
142 };
rbg323_to_bgr8
static av_always_inline void rbg323_to_bgr8(uint8_t *dst, const uint8_t *src, int size)
Definition: sgirledec.c:49
sgirle_decode_init
static av_cold int sgirle_decode_init(AVCodecContext *avctx)
Definition: sgirledec.c:35
INC_XY
#define INC_XY(n)
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
FFCodec
Definition: codec_internal.h:127
AVFrame::flags
int flags
Frame flags, a combination of AV_FRAME_FLAGS.
Definition: frame.h:649
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AV_PIX_FMT_BGR8
@ AV_PIX_FMT_BGR8
packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
Definition: pixfmt.h:90
av_cold
#define av_cold
Definition: attributes.h:90
AV_FRAME_FLAG_KEY
#define AV_FRAME_FLAG_KEY
A flag to mark frames that are keyframes.
Definition: frame.h:628
width
#define width
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:279
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:442
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1618
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:523
codec_internal.h
size
int size
Definition: twinvq_data.h:10344
height
#define height
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
FFMIN3
#define FFMIN3(a, b, c)
Definition: macros.h:50
common.h
av_always_inline
#define av_always_inline
Definition: attributes.h:49
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
AVCodecContext::height
int height
Definition: avcodec.h:625
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:662
avcodec.h
ret
ret
Definition: filter_design.txt:187
RBG323_TO_BGR8
#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:45
ff_sgirle_decoder
const FFCodec ff_sgirle_decoder
Definition: sgirledec.c:134
AVCodecContext
main external API structure.
Definition: avcodec.h:445
sgirle_decode_frame
static int sgirle_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)
Definition: sgirledec.c:113
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AV_CODEC_ID_SGIRLE
@ AV_CODEC_ID_SGIRLE
Definition: codec_id.h:235
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:625
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:385
decode_sgirle8
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:66