FFmpeg
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 "decode.h"
37 #include "internal.h"
38 #include "msrledec.h"
39 #include "libavutil/imgutils.h"
40 
41 typedef struct MsrleContext {
44 
46 
47  uint32_t pal[256];
48 } MsrleContext;
49 
51 {
52  MsrleContext *s = avctx->priv_data;
53  int i;
54 
55  s->avctx = avctx;
56 
57  switch (avctx->bits_per_coded_sample) {
58  case 1:
60  break;
61  case 4:
62  case 8:
63  avctx->pix_fmt = AV_PIX_FMT_PAL8;
64  break;
65  case 24:
66  avctx->pix_fmt = AV_PIX_FMT_BGR24;
67  break;
68  default:
69  av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n");
70  return AVERROR_INVALIDDATA;
71  }
72 
73  s->frame = av_frame_alloc();
74  if (!s->frame)
75  return AVERROR(ENOMEM);
76 
77  if (avctx->extradata_size >= 4)
78  for (i = 0; i < FFMIN(avctx->extradata_size, AVPALETTE_SIZE)/4; i++)
79  s->pal[i] = 0xFFU<<24 | AV_RL32(avctx->extradata+4*i);
80 
81  return 0;
82 }
83 
85  void *data, int *got_frame,
86  AVPacket *avpkt)
87 {
88  const uint8_t *buf = avpkt->data;
89  int buf_size = avpkt->size;
90  MsrleContext *s = avctx->priv_data;
91  int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8;
92  int ret;
93 
94  if (buf_size < 2) //Minimally a end of picture code should be there
95  return AVERROR_INVALIDDATA;
96 
97  if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
98  return ret;
99 
100  if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) {
101  s->frame->palette_has_changed = ff_copy_palette(s->pal, avpkt, avctx);
102 
103  /* make the palette available */
104  memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
105  }
106 
107  /* FIXME how to correctly detect RLE ??? */
108  if (avctx->height * istride == avpkt->size) { /* assume uncompressed */
109  int linesize = av_image_get_linesize(avctx->pix_fmt, avctx->width, 0);
110  uint8_t *ptr = s->frame->data[0];
111  uint8_t *buf = avpkt->data + (avctx->height-1)*istride;
112  int i, j;
113 
114  if (linesize < 0)
115  return linesize;
116 
117  for (i = 0; i < avctx->height; i++) {
118  if (avctx->bits_per_coded_sample == 4) {
119  for (j = 0; j < avctx->width - 1; j += 2) {
120  ptr[j+0] = buf[j>>1] >> 4;
121  ptr[j+1] = buf[j>>1] & 0xF;
122  }
123  if (avctx->width & 1)
124  ptr[j+0] = buf[j>>1] >> 4;
125  } else {
126  memcpy(ptr, buf, linesize);
127  }
128  buf -= istride;
129  ptr += s->frame->linesize[0];
130  }
131  } else {
132  bytestream2_init(&s->gb, buf, buf_size);
133  ff_msrle_decode(avctx, s->frame, avctx->bits_per_coded_sample, &s->gb);
134  }
135 
136  if ((ret = av_frame_ref(data, s->frame)) < 0)
137  return ret;
138 
139  *got_frame = 1;
140 
141  /* report that the buffer was completely consumed */
142  return buf_size;
143 }
144 
146 {
147  MsrleContext *s = avctx->priv_data;
148 
149  av_frame_unref(s->frame);
150 }
151 
153 {
154  MsrleContext *s = avctx->priv_data;
155 
156  /* release the last frame */
157  av_frame_free(&s->frame);
158 
159  return 0;
160 }
161 
163  .name = "msrle",
164  .long_name = NULL_IF_CONFIG_SMALL("Microsoft RLE"),
165  .type = AVMEDIA_TYPE_VIDEO,
166  .id = AV_CODEC_ID_MSRLE,
167  .priv_data_size = sizeof(MsrleContext),
169  .close = msrle_decode_end,
172  .capabilities = AV_CODEC_CAP_DR1,
173 };
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:76
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVCodecContext * avctx
Definition: msrle.c:42
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
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:100
static void flush(AVCodecContext *avctx)
int ff_copy_palette(void *dst, const AVPacket *src, void *logctx)
Check whether the side-data of src contains a palette of size AVPALETTE_SIZE; if so, copy it to dst and return 1; else return 0.
Definition: decode.c:2095
misc image utilities
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
int size
Definition: packet.h:370
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:746
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
static void msrle_decode_flush(AVCodecContext *avctx)
Definition: msrle.c:145
GetByteContext gb
Definition: msrle.c:45
AVCodec.
Definition: codec.h:197
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
uint8_t
#define av_cold
Definition: attributes.h:88
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:191
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
#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:444
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:637
uint8_t * data
Definition: packet.h:369
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1740
#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:84
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:204
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:117
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available...
Definition: decode.c:2000
const char * name
Name of the codec implementation.
Definition: codec.h:204
#define FFMIN(a, b)
Definition: common.h:105
int width
picture width / height.
Definition: avcodec.h:709
#define s(width, name)
Definition: cbs_vp9.c:257
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
AVCodec ff_msrle_decoder
Definition: msrle.c:162
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:349
main external API structure.
Definition: avcodec.h:536
int extradata_size
Definition: avcodec.h:638
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:475
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:554
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:332
AVFrame * frame
Definition: msrle.c:43
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:75
void * priv_data
Definition: avcodec.h:563
static av_cold int msrle_decode_init(AVCodecContext *avctx)
Definition: msrle.c:50
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
static av_cold int msrle_decode_end(AVCodecContext *avctx)
Definition: msrle.c:152
uint32_t pal[256]
Definition: msrle.c:47
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:91
This structure stores compressed data.
Definition: packet.h:346
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators...
Definition: codec.h:52
int i
Definition: input.c:407