FFmpeg: libavcodec/tscc.c Source File

FFmpeg
tscc.c
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1 /*
2  * TechSmith Camtasia decoder
3  * Copyright (c) 2004 Konstantin Shishkov
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  * TechSmith Camtasia decoder
25  *
26  * Fourcc: TSCC
27  *
28  * Codec is very simple:
29  * it codes picture (picture difference, really)
30  * with algorithm almost identical to Windows RLE8,
31  * only without padding and with greater pixel sizes,
32  * then this coded picture is packed with ZLib
33  *
34  * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
35  */
36 
37 #include <stdio.h>
38 #include <stdlib.h>
39 
40 #include "avcodec.h"
41 #include "internal.h"
42 #include "msrledec.h"
43 
44 #include <zlib.h>
45 
46  typedef struct TsccContext {
47 
48   AVCodecContext *avctx;
49   AVFrame *frame;
50 
51  // Bits per pixel
52   int bpp;
53  // Decompressed data size
54   unsigned int decomp_size;
55  // Decompression buffer
56   unsigned char* decomp_buf;
57   GetByteContext gb;
58   int height;
59   z_stream zstream;
60 
61   uint32_t pal[256];
62 } CamtasiaContext;
63 
64  static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
65  AVPacket *avpkt)
66 {
67  const uint8_t *buf = avpkt->data;
68  int buf_size = avpkt->size;
69  CamtasiaContext * const c = avctx->priv_data;
70  AVFrame *frame = c->frame;
71  int ret;
72 
73  if ((ret = ff_reget_buffer(avctx, frame)) < 0)
74  return ret;
75 
76  ret = inflateReset(&c->zstream);
77  if (ret != Z_OK) {
78  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
79  return AVERROR_UNKNOWN;
80  }
81  c->zstream.next_in = buf;
82  c->zstream.avail_in = buf_size;
83  c->zstream.next_out = c->decomp_buf;
84  c->zstream.avail_out = c->decomp_size;
85  ret = inflate(&c->zstream, Z_FINISH);
86  // Z_DATA_ERROR means empty picture
87  if ((ret != Z_OK) && (ret != Z_STREAM_END) && (ret != Z_DATA_ERROR)) {
88  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
89  return AVERROR_UNKNOWN;
90  }
91 
92 
93  if (ret != Z_DATA_ERROR) {
94  bytestream2_init(&c->gb, c->decomp_buf,
95  c->decomp_size - c->zstream.avail_out);
96  ff_msrle_decode(avctx, frame, c->bpp, &c->gb);
97  }
98 
99  /* make the palette available on the way out */
100  if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
101  int size;
102  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
103 
104  if (pal && size == AVPALETTE_SIZE) {
105  frame->palette_has_changed = 1;
106  memcpy(c->pal, pal, AVPALETTE_SIZE);
107  } else if (pal) {
108  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
109  }
110  memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
111  }
112 
113  if ((ret = av_frame_ref(data, frame)) < 0)
114  return ret;
115  *got_frame = 1;
116 
117  /* always report that the buffer was completely consumed */
118  return buf_size;
119 }
120 
121  static av_cold int decode_init(AVCodecContext *avctx)
122 {
123  CamtasiaContext * const c = avctx->priv_data;
124  int zret; // Zlib return code
125 
126  c->avctx = avctx;
127 
128  c->height = avctx->height;
129 
130  // Needed if zlib unused or init aborted before inflateInit
131  memset(&c->zstream, 0, sizeof(z_stream));
132  switch(avctx->bits_per_coded_sample){
133  case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
134  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
135  case 24:
136  avctx->pix_fmt = AV_PIX_FMT_BGR24;
137  break;
138  case 32: avctx->pix_fmt = AV_PIX_FMT_0RGB32; break;
139  default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
140  return AVERROR_PATCHWELCOME;
141  }
142  c->bpp = avctx->bits_per_coded_sample;
143  // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
144  c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
145 
146  /* Allocate decompression buffer */
147  if (c->decomp_size) {
148  if (!(c->decomp_buf = av_malloc(c->decomp_size))) {
149  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
150  return AVERROR(ENOMEM);
151  }
152  }
153 
154  c->zstream.zalloc = Z_NULL;
155  c->zstream.zfree = Z_NULL;
156  c->zstream.opaque = Z_NULL;
157  zret = inflateInit(&c->zstream);
158  if (zret != Z_OK) {
159  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
160  return AVERROR_UNKNOWN;
161  }
162 
163  c->frame = av_frame_alloc();
164 
165  return 0;
166 }
167 
168  static av_cold int decode_end(AVCodecContext *avctx)
169 {
170  CamtasiaContext * const c = avctx->priv_data;
171 
172  av_freep(&c->decomp_buf);
173  av_frame_free(&c->frame);
174 
175  inflateEnd(&c->zstream);
176 
177  return 0;
178 }
179 
180  AVCodec ff_tscc_decoder = {
181  .name = "camtasia",
182  .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
183  .type = AVMEDIA_TYPE_VIDEO,
184  .id = AV_CODEC_ID_TSCC,
185  .priv_data_size = sizeof(CamtasiaContext),
186  .init = decode_init,
187  .close = decode_end,
188  .decode = decode_frame,
189  .capabilities = AV_CODEC_CAP_DR1,
190 };
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
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
data
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
AVPacket::size
int size
Definition: avcodec.h:1431
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1727
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
CamtasiaContext::decomp_buf
unsigned char * decomp_buf
Definition: tscc.c:56
AVCodec
AVCodec.
Definition: avcodec.h:3408
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
ff_reget_buffer
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:1938
CamtasiaContext::zstream
z_stream zstream
Definition: tscc.c:59
uint8_t
uint8_t
Definition: audio_convert.c:194
av_cold
#define av_cold
Definition: attributes.h:82
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
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:441
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: tscc.c:121
frame
static AVFrame * frame
Definition: demuxing_decoding.c:53
AVPacket::data
uint8_t * data
Definition: avcodec.h:1430
inflate
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord)
Definition: vf_neighbor.c:129
size
ptrdiff_t size
Definition: opengl_enc.c:101
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2734
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AV_PKT_DATA_PALETTE
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1149
AVERROR
#define AVERROR(e)
Definition: error.h:43
av_packet_get_side_data
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:350
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
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:186
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3415
CamtasiaContext::avctx
AVCodecContext * avctx
Definition: tscc.c:48
CamtasiaContext::gb
GetByteContext gb
Definition: tscc.c:57
ff_tscc_decoder
AVCodec ff_tscc_decoder
Definition: tscc.c:180
CamtasiaContext::bpp
int bpp
Definition: tscc.c:52
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:1690
AV_CODEC_ID_TSCC
Definition: avcodec.h:274
AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:65
AVCodecContext::height
int height
Definition: avcodec.h:1690
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
avcodec.h
Libavcodec external API header.
AVCodecContext
main external API structure.
Definition: avcodec.h:1518
buf
void * buf
Definition: avisynth_c.h:690
CamtasiaContext::pal
uint32_t pal[256]
Definition: tscc.c:61
AVFrame::palette_has_changed
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:375
CamtasiaContext::frame
AVFrame * frame
Definition: tscc.c:49
CamtasiaContext::decomp_size
unsigned int decomp_size
Definition: tscc.c:54
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
internal.h
common internal api header.
if
if(ret< 0)
Definition: vf_mcdeint.c:279
c
static double c[64]
Definition: vsrc_mptestsrc.c:87
AV_PIX_FMT_RGB555
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:356
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1545
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Definition: tscc.c:168
CamtasiaContext::height
int height
Definition: tscc.c:58
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1407
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:959
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: tscc.c:64
AV_PIX_FMT_0RGB32
#define AV_PIX_FMT_0RGB32
Definition: pixfmt.h:346
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