FFmpeg: libavcodec/rl2.c Source File

FFmpeg
rl2.c
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1 /*
2  * RL2 Video Decoder
3  * Copyright (C) 2008 Sascha Sommer (saschasommer@freenet.de)
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  * RL2 Video Decoder
25  * @author Sascha Sommer (saschasommer@freenet.de)
26  * @see http://wiki.multimedia.cx/index.php?title=RL2
27  */
28 
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 
33 #include "libavutil/internal.h"
34 #include "libavutil/intreadwrite.h"
35 #include "libavutil/mem.h"
36 #include "avcodec.h"
37 #include "internal.h"
38 
39 
40  #define EXTRADATA1_SIZE (6 + 256 * 3) ///< video base, clr count, palette
41 
42  typedef struct Rl2Context {
43   AVCodecContext *avctx;
44 
45   uint16_t video_base; ///< initial drawing offset
46   uint32_t clr_count; ///< number of used colors (currently unused)
47   uint8_t *back_frame; ///< background frame
48   uint32_t palette[AVPALETTE_COUNT];
49 } Rl2Context;
50 
51 /**
52  * Run Length Decode a single 320x200 frame
53  * @param s rl2 context
54  * @param in input buffer
55  * @param size input buffer size
56  * @param out output buffer
57  * @param stride stride of the output buffer
58  * @param video_base offset of the rle data inside the frame
59  */
60  static void rl2_rle_decode(Rl2Context *s, const uint8_t *in, int size,
61  uint8_t *out, int stride, int video_base)
62 {
63  int base_x = video_base % s->avctx->width;
64  int base_y = video_base / s->avctx->width;
65  int stride_adj = stride - s->avctx->width;
66  int i;
67  const uint8_t *back_frame = s->back_frame;
68  const uint8_t *in_end = in + size;
69  const uint8_t *out_end = out + stride * s->avctx->height;
70  uint8_t *line_end;
71 
72  /** copy start of the background frame */
73  for (i = 0; i <= base_y; i++) {
74  if (s->back_frame)
75  memcpy(out, back_frame, s->avctx->width);
76  out += stride;
77  back_frame += s->avctx->width;
78  }
79  back_frame += base_x - s->avctx->width;
80  line_end = out - stride_adj;
81  out += base_x - stride;
82 
83  /** decode the variable part of the frame */
84  while (in < in_end) {
85  uint8_t val = *in++;
86  int len = 1;
87  if (val >= 0x80) {
88  if (in >= in_end)
89  break;
90  len = *in++;
91  if (!len)
92  break;
93  }
94 
95  if (len >= out_end - out)
96  break;
97 
98  if (s->back_frame)
99  val |= 0x80;
100  else
101  val &= ~0x80;
102 
103  while (len--) {
104  *out++ = (val == 0x80) ? *back_frame : val;
105  back_frame++;
106  if (out == line_end) {
107  out += stride_adj;
108  line_end += stride;
109  if (len >= out_end - out)
110  break;
111  }
112  }
113  }
114 
115  /** copy the rest from the background frame */
116  if (s->back_frame) {
117  while (out < out_end) {
118  memcpy(out, back_frame, line_end - out);
119  back_frame += line_end - out;
120  out = line_end + stride_adj;
121  line_end += stride;
122  }
123  }
124 }
125 
126 
127 /**
128  * Initialize the decoder
129  * @param avctx decoder context
130  * @return 0 success, -1 on error
131  */
132  static av_cold int rl2_decode_init(AVCodecContext *avctx)
133 {
134  Rl2Context *s = avctx->priv_data;
135  int back_size;
136  int i;
137 
138  s->avctx = avctx;
139  avctx->pix_fmt = AV_PIX_FMT_PAL8;
140 
141  /** parse extra data */
142  if (!avctx->extradata || avctx->extradata_size < EXTRADATA1_SIZE) {
143  av_log(avctx, AV_LOG_ERROR, "invalid extradata size\n");
144  return AVERROR(EINVAL);
145  }
146 
147  /** get frame_offset */
148  s->video_base = AV_RL16(&avctx->extradata[0]);
149  s->clr_count = AV_RL32(&avctx->extradata[2]);
150 
151  if (s->video_base >= avctx->width * avctx->height) {
152  av_log(avctx, AV_LOG_ERROR, "invalid video_base\n");
153  return AVERROR_INVALIDDATA;
154  }
155 
156  /** initialize palette */
157  for (i = 0; i < AVPALETTE_COUNT; i++)
158  s->palette[i] = 0xFFU << 24 | AV_RB24(&avctx->extradata[6 + i * 3]);
159 
160  /** decode background frame if present */
161  back_size = avctx->extradata_size - EXTRADATA1_SIZE;
162 
163  if (back_size > 0) {
164  uint8_t *back_frame = av_mallocz(avctx->width*avctx->height);
165  if (!back_frame)
166  return AVERROR(ENOMEM);
167  rl2_rle_decode(s, avctx->extradata + EXTRADATA1_SIZE, back_size,
168  back_frame, avctx->width, 0);
169  s->back_frame = back_frame;
170  }
171  return 0;
172 }
173 
174 
175  static int rl2_decode_frame(AVCodecContext *avctx,
176  void *data, int *got_frame,
177  AVPacket *avpkt)
178 {
179  AVFrame *frame = data;
180  const uint8_t *buf = avpkt->data;
181  int ret, buf_size = avpkt->size;
182  Rl2Context *s = avctx->priv_data;
183 
184  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
185  return ret;
186 
187  /** run length decode */
188  rl2_rle_decode(s, buf, buf_size, frame->data[0], frame->linesize[0],
189  s->video_base);
190 
191  /** make the palette available on the way out */
192  memcpy(frame->data[1], s->palette, AVPALETTE_SIZE);
193 
194  *got_frame = 1;
195 
196  /** report that the buffer was completely consumed */
197  return buf_size;
198 }
199 
200 
201 /**
202  * Uninit decoder
203  * @param avctx decoder context
204  * @return 0 success, -1 on error
205  */
206  static av_cold int rl2_decode_end(AVCodecContext *avctx)
207 {
208  Rl2Context *s = avctx->priv_data;
209 
210  av_freep(&s->back_frame);
211 
212  return 0;
213 }
214 
215 
216  AVCodec ff_rl2_decoder = {
217  .name = "rl2",
218  .long_name = NULL_IF_CONFIG_SMALL("RL2 video"),
219  .type = AVMEDIA_TYPE_VIDEO,
220  .id = AV_CODEC_ID_RL2,
221  .priv_data_size = sizeof(Rl2Context),
222  .init = rl2_decode_init,
223  .close = rl2_decode_end,
224  .decode = rl2_decode_frame,
225  .capabilities = AV_CODEC_CAP_DR1,
226 };
val
const char const char void * val
Definition: avisynth_c.h:634
s
const char * s
Definition: avisynth_c.h:631
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:181
data
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
mem.h
memory handling functions
EXTRADATA1_SIZE
#define EXTRADATA1_SIZE
video base, clr count, palette
Definition: rl2.c:40
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
AVPacket::size
int size
Definition: avcodec.h:1468
rl2_decode_end
static av_cold int rl2_decode_end(AVCodecContext *avctx)
Uninit decoder.
Definition: rl2.c:206
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1752
AVCodec
AVCodec.
Definition: avcodec.h:3392
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
uint8_t
uint8_t
Definition: audio_convert.c:194
av_cold
#define av_cold
Definition: attributes.h:82
AV_PIX_FMT_PAL8
8 bit with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:74
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:33
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1647
ff_rl2_decoder
AVCodec ff_rl2_decoder
Definition: rl2.c:216
frame
static AVFrame * frame
Definition: demuxing_decoding.c:53
AVPacket::data
uint8_t * data
Definition: avcodec.h:1467
size
ptrdiff_t size
Definition: opengl_enc.c:101
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
Rl2Context::avctx
AVCodecContext * avctx
Definition: rl2.c:43
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
rl2_rle_decode
static void rl2_rle_decode(Rl2Context *s, const uint8_t *in, int size, uint8_t *out, int stride, int video_base)
Run Length Decode a single 320x200 frame.
Definition: rl2.c:60
AVERROR
#define AVERROR(e)
Definition: error.h:43
AV_CODEC_ID_RL2
Definition: avcodec.h:221
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3399
Rl2Context
Definition: rl2.c:42
internal.h
common internal API header
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:1711
rl2_decode_frame
static int rl2_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: rl2.c:175
AVCodecContext::height
int height
Definition: avcodec.h:1711
Rl2Context::back_frame
uint8_t * back_frame
background frame
Definition: rl2.c:47
out
FILE * out
Definition: movenc-test.c:54
Rl2Context::video_base
uint16_t video_base
initial drawing offset
Definition: rl2.c:45
avcodec.h
Libavcodec external API header.
AV_RB24
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:87
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:209
AVCodecContext
main external API structure.
Definition: avcodec.h:1532
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:894
in
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
Definition: audio_convert.c:194
buf
void * buf
Definition: avisynth_c.h:553
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:1648
Rl2Context::palette
uint32_t palette[AVPALETTE_COUNT]
Definition: rl2.c:48
AVPALETTE_COUNT
#define AVPALETTE_COUNT
Definition: pixfmt.h:34
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:192
decode
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:572
stride
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:105
internal.h
common internal api header.
rl2_decode_init
static av_cold int rl2_decode_init(AVCodecContext *avctx)
Initialize the decoder.
Definition: rl2.c:132
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1574
Rl2Context::clr_count
uint32_t clr_count
number of used colors (currently unused)
Definition: rl2.c:46
len
int len
Definition: vorbis_enc_data.h:452
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AVMEDIA_TYPE_VIDEO
Definition: avutil.h:193
stride
#define stride
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1444
av_mallocz
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:252
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:856
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