msrle.c
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1 /*
2  * Microsoft RLE video decoder
3  * Copyright (C) 2003 the ffmpeg project
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 
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 
35 #include "avcodec.h"
36 #include "dsputil.h"
37 #include "msrledec.h"
38 
39 typedef struct MsrleContext {
42 
44  const unsigned char *buf;
45  int size;
46 
47  uint32_t pal[256];
48 } MsrleContext;
49 
51 {
52  MsrleContext *s = avctx->priv_data;
53 
54  s->avctx = avctx;
55 
56  switch (avctx->bits_per_coded_sample) {
57  case 4:
58  case 8:
59  avctx->pix_fmt = PIX_FMT_PAL8;
60  break;
61  case 24:
62  avctx->pix_fmt = PIX_FMT_BGR24;
63  break;
64  default:
65  av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n");
66  return -1;
67  }
68 
69  s->frame.data[0] = NULL;
70 
71  return 0;
72 }
73 
75  void *data, int *data_size,
76  AVPacket *avpkt)
77 {
78  const uint8_t *buf = avpkt->data;
79  int buf_size = avpkt->size;
80  MsrleContext *s = avctx->priv_data;
81  int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8;
82 
83  s->buf = buf;
84  s->size = buf_size;
85 
86  s->frame.reference = 1;
88  if (avctx->reget_buffer(avctx, &s->frame)) {
89  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
90  return -1;
91  }
92 
93  if (avctx->bits_per_coded_sample <= 8) {
94  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
95 
96  if (pal) {
98  memcpy(s->pal, pal, AVPALETTE_SIZE);
99  }
100 
101  /* make the palette available */
102  memcpy(s->frame.data[1], s->pal, AVPALETTE_SIZE);
103  }
104 
105  /* FIXME how to correctly detect RLE ??? */
106  if (avctx->height * istride == avpkt->size) { /* assume uncompressed */
107  int linesize = avctx->width * avctx->bits_per_coded_sample / 8;
108  uint8_t *ptr = s->frame.data[0];
109  uint8_t *buf = avpkt->data + (avctx->height-1)*istride;
110  int i, j;
111 
112  for (i = 0; i < avctx->height; i++) {
113  if (avctx->bits_per_coded_sample == 4) {
114  for (j = 0; j < avctx->width - 1; j += 2) {
115  ptr[j+0] = buf[j>>1] >> 4;
116  ptr[j+1] = buf[j>>1] & 0xF;
117  }
118  if (avctx->width & 1)
119  ptr[j+0] = buf[j>>1] >> 4;
120  } else {
121  memcpy(ptr, buf, linesize);
122  }
123  buf -= istride;
124  ptr += s->frame.linesize[0];
125  }
126  } else {
127  bytestream2_init(&s->gb, buf, buf_size);
128  ff_msrle_decode(avctx, (AVPicture*)&s->frame, avctx->bits_per_coded_sample, &s->gb);
129  }
130 
131  *data_size = sizeof(AVFrame);
132  *(AVFrame*)data = s->frame;
133 
134  /* report that the buffer was completely consumed */
135  return buf_size;
136 }
137 
139 {
140  MsrleContext *s = avctx->priv_data;
141 
142  /* release the last frame */
143  if (s->frame.data[0])
144  avctx->release_buffer(avctx, &s->frame);
145 
146  return 0;
147 }
148 
150  .name = "msrle",
151  .type = AVMEDIA_TYPE_VIDEO,
152  .id = CODEC_ID_MSRLE,
153  .priv_data_size = sizeof(MsrleContext),
157  .capabilities = CODEC_CAP_DR1,
158  .long_name= NULL_IF_CONFIG_SMALL("Microsoft RLE"),
159 };
enum PixelFormat pix_fmt
Pixel format, see PIX_FMT_xxx.
Definition: avcodec.h:1426
AVFrame frame
Definition: msrle.c:41
#define FF_BUFFER_HINTS_VALID
Definition: avcodec.h:880
AVCodecContext * avctx
Definition: msrle.c:40
Audio Video Frame.
Definition: avcodec.h:985
int buffer_hints
codec suggestion on buffer type if != 0
Definition: avcodec.h:1195
void(* release_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called to release buffers which were allocated with get_buffer.
Definition: avcodec.h:1737
int size
Definition: avcodec.h:909
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:138
GetByteContext gb
Definition: msrle.c:43
four components are given, that's all.
Definition: avcodec.h:3367
int size
Definition: msrle.c:45
AVCodec.
Definition: avcodec.h:3189
#define FFALIGN(x, a)
Definition: common.h:60
int(* reget_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called at the beginning of a frame to get cr buffer for it.
Definition: avcodec.h:2336
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:228
#define av_cold
Definition: attributes.h:71
const char data[16]
Definition: mxf.c:60
uint8_t * data
Definition: avcodec.h:908
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1974
static int init(AVCodecParserContext *s)
Definition: h264_parser.c:336
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:719
int reference
is this picture used as reference The values for this are the same as the MpegEncContext.picture_structure variable, that is 1->top field, 2->bottom field, 3->frame/both fields.
Definition: avcodec.h:1074
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:191
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:140
const char * name
Name of the codec implementation.
Definition: avcodec.h:3196
static int msrle_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
Definition: msrle.c:74
int width
picture width / height.
Definition: avcodec.h:1408
struct AVFrame AVFrame
Audio Video Frame.
AVCodec ff_msrle_decoder
Definition: msrle.c:149
const unsigned char * buf
Definition: msrle.c:44
#define FF_BUFFER_HINTS_REUSABLE
Definition: avcodec.h:883
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:185
NULL
Definition: eval.c:50
external API header
int linesize[AV_NUM_DATA_POINTERS]
Size, in bytes, of the data for each picture/channel plane.
Definition: avcodec.h:1008
main external API structure.
Definition: avcodec.h:1329
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:327
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:111
#define FF_BUFFER_HINTS_PRESERVE
Definition: avcodec.h:882
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: avcodec.h:1188
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:67
struct MsrleContext MsrleContext
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: avcodec.h:997
#define AVPALETTE_SIZE
Definition: avcodec.h:3372
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:75
DSP utils.
void * priv_data
Definition: avcodec.h:1531
int ff_msrle_decode(AVCodecContext *avctx, AVPicture *pic, int depth, GetByteContext *gb)
Decode stream in MS RLE format into frame.
Definition: msrledec.c:246
static av_cold int msrle_decode_init(AVCodecContext *avctx)
Definition: msrle.c:50
static av_cold int msrle_decode_end(AVCodecContext *avctx)
Definition: msrle.c:138
uint32_t pal[256]
Definition: msrle.c:47