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 <string.h>
32 
33 #include "avcodec.h"
34 #include "codec_internal.h"
35 #include "decode.h"
36 #include "msrledec.h"
37 #include "libavutil/imgutils.h"
38 
39 typedef struct MsrleContext {
42 
44 
45  uint32_t pal[256];
46 } MsrleContext;
47 
49 {
50  MsrleContext *s = avctx->priv_data;
51  int i;
52 
53  s->avctx = avctx;
54 
55  switch (avctx->bits_per_coded_sample) {
56  case 1:
58  break;
59  case 4:
60  case 8:
61  avctx->pix_fmt = AV_PIX_FMT_PAL8;
62  break;
63  case 24:
64  avctx->pix_fmt = AV_PIX_FMT_BGR24;
65  break;
66  default:
67  av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n");
68  return AVERROR_INVALIDDATA;
69  }
70 
71  s->frame = av_frame_alloc();
72  if (!s->frame)
73  return AVERROR(ENOMEM);
74 
75  if (avctx->extradata_size >= 4)
76  for (i = 0; i < FFMIN(avctx->extradata_size, AVPALETTE_SIZE)/4; i++)
77  s->pal[i] = 0xFFU<<24 | AV_RL32(avctx->extradata+4*i);
78 
79  return 0;
80 }
81 
82 static int msrle_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
83  int *got_frame, AVPacket *avpkt)
84 {
85  const uint8_t *buf = avpkt->data;
86  int buf_size = avpkt->size;
87  MsrleContext *s = avctx->priv_data;
88  int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8;
89  int ret;
90 
91  if (buf_size < 2) //Minimally a end of picture code should be there
92  return AVERROR_INVALIDDATA;
93 
94  if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
95  return ret;
96 
97  if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) {
98 #if FF_API_PALETTE_HAS_CHANGED
100  s->frame->palette_has_changed =
101 #endif
102  ff_copy_palette(s->pal, avpkt, avctx);
103 #if FF_API_PALETTE_HAS_CHANGED
105 #endif
106 
107  /* make the palette available */
108  memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
109  }
110 
111  /* FIXME how to correctly detect RLE ??? */
112  if (avctx->height * istride == avpkt->size) { /* assume uncompressed */
113  int linesize = av_image_get_linesize(avctx->pix_fmt, avctx->width, 0);
114  uint8_t *ptr = s->frame->data[0];
115  const uint8_t *buf = avpkt->data + (avctx->height-1)*istride;
116  int i, j;
117 
118  if (linesize < 0)
119  return linesize;
120 
121  for (i = 0; i < avctx->height; i++) {
122  if (avctx->bits_per_coded_sample == 4) {
123  for (j = 0; j < avctx->width - 1; j += 2) {
124  ptr[j+0] = buf[j>>1] >> 4;
125  ptr[j+1] = buf[j>>1] & 0xF;
126  }
127  if (avctx->width & 1)
128  ptr[j+0] = buf[j>>1] >> 4;
129  } else {
130  memcpy(ptr, buf, linesize);
131  }
132  buf -= istride;
133  ptr += s->frame->linesize[0];
134  }
135  } else {
136  bytestream2_init(&s->gb, buf, buf_size);
137  ff_msrle_decode(avctx, s->frame, avctx->bits_per_coded_sample, &s->gb);
138  }
139 
140  if ((ret = av_frame_ref(rframe, s->frame)) < 0)
141  return ret;
142 
143  *got_frame = 1;
144 
145  /* report that the buffer was completely consumed */
146  return buf_size;
147 }
148 
150 {
151  MsrleContext *s = avctx->priv_data;
152 
153  av_frame_unref(s->frame);
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  .p.name = "msrle",
168  CODEC_LONG_NAME("Microsoft RLE"),
169  .p.type = AVMEDIA_TYPE_VIDEO,
170  .p.id = AV_CODEC_ID_MSRLE,
171  .priv_data_size = sizeof(MsrleContext),
173  .close = msrle_decode_end,
175  .flush = msrle_decode_flush,
176  .p.capabilities = AV_CODEC_CAP_DR1,
177 };
FF_ENABLE_DEPRECATION_WARNINGS
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:73
AVERROR
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
GetByteContext
Definition: bytestream.h:33
msrle_decode_frame
static int msrle_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)
Definition: msrle.c:82
MsrleContext::frame
AVFrame * frame
Definition: msrle.c:41
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:100
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
AV_PIX_FMT_MONOWHITE
@ AV_PIX_FMT_MONOWHITE
Y , 1bpp, 0 is white, 1 is black, in each byte pixels are ordered from the msb to the lsb.
Definition: pixfmt.h:82
FFCodec
Definition: codec_internal.h:127
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:76
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
MsrleContext::pal
uint32_t pal[256]
Definition: msrle.c:45
msrle_decode_end
static av_cold int msrle_decode_end(AVCodecContext *avctx)
Definition: msrle.c:156
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:88
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:547
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:306
s
#define s(width, name)
Definition: cbs_vp9.c:198
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
msrledec.h
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:365
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
MsrleContext::gb
GetByteContext gb
Definition: msrle.c:43
av_frame_ref
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:361
codec_internal.h
ff_msrle_decoder
const FFCodec ff_msrle_decoder
Definition: msrle.c:166
AV_CODEC_ID_MSRLE
@ AV_CODEC_ID_MSRLE
Definition: codec_id.h:97
msrle_decode_init
static av_cold int msrle_decode_init(AVCodecContext *avctx)
Definition: msrle.c:48
av_image_get_linesize
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
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1514
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:546
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
MsrleContext::avctx
AVCodecContext * avctx
Definition: msrle.c:40
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:622
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
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:84
ff_reget_buffer
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:1736
ret
ret
Definition: filter_design.txt:187
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
MsrleContext
Definition: msrle.c:39
AVCodecContext
main external API structure.
Definition: avcodec.h:445
msrle_decode_flush
static void msrle_decode_flush(AVCodecContext *avctx)
Definition: msrle.c:149
FF_DISABLE_DEPRECATION_WARNINGS
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:72
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:78
ff_msrle_decode
int ff_msrle_decode(AVCodecContext *avctx, AVFrame *pic, int depth, GetByteContext *gb)
Decode stream in MS RLE format into frame.
Definition: msrledec.c:249
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:625
imgutils.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ff_copy_palette
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,...
Definition: decode.c:1824