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 "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 (buf_size < 2) //Minimally a end of picture code should be there
99  return AVERROR_INVALIDDATA;
100 
101  if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
102  return ret;
103 
104  if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) {
105  int size;
106  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
107 
108  if (pal && size == AVPALETTE_SIZE) {
109  s->frame->palette_has_changed = 1;
110  memcpy(s->pal, pal, AVPALETTE_SIZE);
111  } else if (pal) {
112  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
113  }
114  /* make the palette available */
115  memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
116  }
117 
118  /* FIXME how to correctly detect RLE ??? */
119  if (avctx->height * istride == avpkt->size) { /* assume uncompressed */
120  int linesize = av_image_get_linesize(avctx->pix_fmt, avctx->width, 0);
121  uint8_t *ptr = s->frame->data[0];
122  uint8_t *buf = avpkt->data + (avctx->height-1)*istride;
123  int i, j;
124 
125  if (linesize < 0)
126  return linesize;
127 
128  for (i = 0; i < avctx->height; i++) {
129  if (avctx->bits_per_coded_sample == 4) {
130  for (j = 0; j < avctx->width - 1; j += 2) {
131  ptr[j+0] = buf[j>>1] >> 4;
132  ptr[j+1] = buf[j>>1] & 0xF;
133  }
134  if (avctx->width & 1)
135  ptr[j+0] = buf[j>>1] >> 4;
136  } else {
137  memcpy(ptr, buf, linesize);
138  }
139  buf -= istride;
140  ptr += s->frame->linesize[0];
141  }
142  } else {
143  bytestream2_init(&s->gb, buf, buf_size);
144  ff_msrle_decode(avctx, s->frame, avctx->bits_per_coded_sample, &s->gb);
145  }
146 
147  if ((ret = av_frame_ref(data, s->frame)) < 0)
148  return ret;
149 
150  *got_frame = 1;
151 
152  /* report that the buffer was completely consumed */
153  return buf_size;
154 }
155 
157 {
158  MsrleContext *s = avctx->priv_data;
159 
160  /* release the last frame */
161  av_frame_free(&s->frame);
162 
163  return 0;
164 }
165 
167  .name = "msrle",
168  .long_name = NULL_IF_CONFIG_SMALL("Microsoft RLE"),
169  .type = AVMEDIA_TYPE_VIDEO,
170  .id = AV_CODEC_ID_MSRLE,
171  .priv_data_size = sizeof(MsrleContext),
173  .close = msrle_decode_end,
175  .capabilities = AV_CODEC_CAP_DR1,
176 };
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:41
This structure describes decoded (raw) audio or video data.
Definition: frame.h:268
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
misc image utilities
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1478
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
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:3477
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
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: decode.c:2011
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:189
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:443
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1666
uint8_t * data
Definition: avcodec.h:1477
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2785
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:260
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
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1190
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:350
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3484
#define FFMIN(a, b)
Definition: common.h:96
int width
picture width / height.
Definition: avcodec.h:1738
#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:166
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:299
main external API structure.
Definition: avcodec.h:1565
int extradata_size
Definition: avcodec.h:1667
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:425
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
AVFrame * frame
Definition: msrle.c:42
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:1592
static av_cold int msrle_decode_init(AVCodecContext *avctx)
Definition: msrle.c:51
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:156
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:1454
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981