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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 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  * MS RLE video decoder by Mike Melanson (melanson@pcisys.net)
25  * For more information about the MS RLE format, visit:
26  * http://www.pcisys.net/~melanson/codecs/
27  *
28  * The MS RLE decoder outputs PAL8 colorspace data.
29  */
30 
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 
35 #include "avcodec.h"
36 #include "internal.h"
37 #include "msrledec.h"
38 #include "libavutil/imgutils.h"
39 
40 typedef struct MsrleContext {
43 
45  const unsigned char *buf;
46  int size;
47 
48  uint32_t pal[256];
49 } MsrleContext;
50 
52 {
53  MsrleContext *s = avctx->priv_data;
54  int i;
55 
56  s->avctx = avctx;
57 
58  switch (avctx->bits_per_coded_sample) {
59  case 1:
61  break;
62  case 4:
63  case 8:
64  avctx->pix_fmt = AV_PIX_FMT_PAL8;
65  break;
66  case 24:
67  avctx->pix_fmt = AV_PIX_FMT_BGR24;
68  break;
69  default:
70  av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n");
71  return AVERROR_INVALIDDATA;
72  }
73 
74  s->frame = av_frame_alloc();
75  if (!s->frame)
76  return AVERROR(ENOMEM);
77 
78  if (avctx->extradata_size >= 4)
79  for (i = 0; i < FFMIN(avctx->extradata_size, AVPALETTE_SIZE)/4; i++)
80  s->pal[i] = 0xFFU<<24 | AV_RL32(avctx->extradata+4*i);
81 
82  return 0;
83 }
84 
86  void *data, int *got_frame,
87  AVPacket *avpkt)
88 {
89  const uint8_t *buf = avpkt->data;
90  int buf_size = avpkt->size;
91  MsrleContext *s = avctx->priv_data;
92  int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8;
93  int ret;
94 
95  s->buf = buf;
96  s->size = buf_size;
97 
98  if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
99  return ret;
100 
101  if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) {
103 
104  if (pal) {
105  s->frame->palette_has_changed = 1;
106  memcpy(s->pal, pal, AVPALETTE_SIZE);
107  }
108  /* make the palette available */
109  memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
110  }
111 
112  /* FIXME how to correctly detect RLE ??? */
113  if (avctx->height * istride == avpkt->size) { /* assume uncompressed */
114  int linesize = av_image_get_linesize(avctx->pix_fmt, avctx->width, 0);
115  uint8_t *ptr = s->frame->data[0];
116  uint8_t *buf = avpkt->data + (avctx->height-1)*istride;
117  int i, j;
118 
119  if (linesize < 0)
120  return linesize;
121 
122  for (i = 0; i < avctx->height; i++) {
123  if (avctx->bits_per_coded_sample == 4) {
124  for (j = 0; j < avctx->width - 1; j += 2) {
125  ptr[j+0] = buf[j>>1] >> 4;
126  ptr[j+1] = buf[j>>1] & 0xF;
127  }
128  if (avctx->width & 1)
129  ptr[j+0] = buf[j>>1] >> 4;
130  } else {
131  memcpy(ptr, buf, linesize);
132  }
133  buf -= istride;
134  ptr += s->frame->linesize[0];
135  }
136  } else {
137  bytestream2_init(&s->gb, buf, buf_size);
138  ff_msrle_decode(avctx, s->frame, avctx->bits_per_coded_sample, &s->gb);
139  }
140 
141  if ((ret = av_frame_ref(data, s->frame)) < 0)
142  return ret;
143 
144  *got_frame = 1;
145 
146  /* report that the buffer was completely consumed */
147  return buf_size;
148 }
149 
151 {
152  MsrleContext *s = avctx->priv_data;
153 
154  /* release the last frame */
155  av_frame_free(&s->frame);
156 
157  return 0;
158 }
159 
161  .name = "msrle",
162  .long_name = NULL_IF_CONFIG_SMALL("Microsoft RLE"),
163  .type = AVMEDIA_TYPE_VIDEO,
164  .id = AV_CODEC_ID_MSRLE,
165  .priv_data_size = sizeof(MsrleContext),
167  .close = msrle_decode_end,
169  .capabilities = AV_CODEC_CAP_DR1,
170 };
#define NULL
Definition: coverity.c:32
int av_image_get_linesize(enum AVPixelFormat pix_fmt, int width, int plane)
Compute the size of an image line with format pix_fmt and width width for the plane plane...
Definition: imgutils.c:75
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVCodecContext * avctx
Definition: msrle.c:41
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
int ff_msrle_decode(AVCodecContext *avctx, AVFrame *pic, int depth, GetByteContext *gb)
Decode stream in MS RLE format into frame.
Definition: msrledec.c:249
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
misc image utilities
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1601
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1903
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
GetByteContext gb
Definition: msrle.c:44
int size
Definition: msrle.c:46
AVCodec.
Definition: avcodec.h:3589
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:141
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:375
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1790
uint8_t * data
Definition: avcodec.h:1600
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:3069
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
static int msrle_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: msrle.c:85
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:154
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
const char * name
Name of the codec implementation.
Definition: avcodec.h:3596
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
Identical in function to av_frame_make_writable(), except it uses ff_get_buffer() to allocate the buf...
Definition: utils.c:983
#define FFMIN(a, b)
Definition: common.h:96
int width
picture width / height.
Definition: avcodec.h:1862
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:65
AVCodec ff_msrle_decoder
Definition: msrle.c:160
const unsigned char * buf
Definition: msrle.c:45
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:215
main external API structure.
Definition: avcodec.h:1675
void * buf
Definition: avisynth_c.h:690
int extradata_size
Definition: avcodec.h:1791
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:328
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
AVFrame * frame
Definition: msrle.c:42
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:750
common internal api header.
Y , 1bpp, 0 is white, 1 is black, in each byte pixels are ordered from the msb to the lsb...
Definition: pixfmt.h:71
void * priv_data
Definition: avcodec.h:1717
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:338
static av_cold int msrle_decode_init(AVCodecContext *avctx)
Definition: msrle.c:51
static av_cold int msrle_decode_end(AVCodecContext *avctx)
Definition: msrle.c:150
uint32_t pal[256]
Definition: msrle.c:48
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1577
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:958