tscc.c
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1 /*
2  * TechSmith Camtasia decoder
3  * Copyright (c) 2004 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
38 #include <stdio.h>
39 #include <stdlib.h>
40 
41 #include "avcodec.h"
42 #include "msrledec.h"
43 
44 #include <zlib.h>
45 
46 
47 /*
48  * Decoder context
49  */
50 typedef struct TsccContext {
51 
54 
55  // Bits per pixel
56  int bpp;
57  // Decompressed data size
58  unsigned int decomp_size;
59  // Decompression buffer
60  unsigned char* decomp_buf;
62  int height;
63  z_stream zstream;
64 
65  uint32_t pal[256];
67 
68 /*
69  *
70  * Decode a frame
71  *
72  */
73 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
74 {
75  const uint8_t *buf = avpkt->data;
76  int buf_size = avpkt->size;
77  CamtasiaContext * const c = avctx->priv_data;
78  const unsigned char *encoded = buf;
79  int zret; // Zlib return code
80  int len = buf_size;
81 
82  if(c->pic.data[0])
83  avctx->release_buffer(avctx, &c->pic);
84 
85  c->pic.reference = 1;
87  if(avctx->get_buffer(avctx, &c->pic) < 0){
88  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
89  return -1;
90  }
91 
92  zret = inflateReset(&c->zstream);
93  if (zret != Z_OK) {
94  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
95  return -1;
96  }
97  c->zstream.next_in = encoded;
98  c->zstream.avail_in = len;
99  c->zstream.next_out = c->decomp_buf;
100  c->zstream.avail_out = c->decomp_size;
101  zret = inflate(&c->zstream, Z_FINISH);
102  // Z_DATA_ERROR means empty picture
103  if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
104  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
105  return -1;
106  }
107 
108 
109  if (zret != Z_DATA_ERROR) {
111  c->decomp_size - c->zstream.avail_out);
112  ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, &c->gb);
113  }
114 
115  /* make the palette available on the way out */
116  if (c->avctx->pix_fmt == PIX_FMT_PAL8) {
117  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
118 
119  if (pal) {
120  c->pic.palette_has_changed = 1;
121  memcpy(c->pal, pal, AVPALETTE_SIZE);
122  }
123  memcpy(c->pic.data[1], c->pal, AVPALETTE_SIZE);
124  }
125 
126  *data_size = sizeof(AVFrame);
127  *(AVFrame*)data = c->pic;
128 
129  /* always report that the buffer was completely consumed */
130  return buf_size;
131 }
132 
133 
134 
135 /*
136  *
137  * Init tscc decoder
138  *
139  */
141 {
142  CamtasiaContext * const c = avctx->priv_data;
143  int zret; // Zlib return code
144 
145  c->avctx = avctx;
146 
147  c->height = avctx->height;
148 
149  // Needed if zlib unused or init aborted before inflateInit
150  memset(&c->zstream, 0, sizeof(z_stream));
151  switch(avctx->bits_per_coded_sample){
152  case 8: avctx->pix_fmt = PIX_FMT_PAL8; break;
153  case 16: avctx->pix_fmt = PIX_FMT_RGB555; break;
154  case 24:
155  avctx->pix_fmt = PIX_FMT_BGR24;
156  break;
157  case 32: avctx->pix_fmt = PIX_FMT_RGB32; break;
158  default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
159  return -1;
160  }
161  c->bpp = avctx->bits_per_coded_sample;
162  // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
163  c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
164 
165  /* Allocate decompression buffer */
166  if (c->decomp_size) {
167  if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {
168  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
169  return 1;
170  }
171  }
172 
173  c->zstream.zalloc = Z_NULL;
174  c->zstream.zfree = Z_NULL;
175  c->zstream.opaque = Z_NULL;
176  zret = inflateInit(&c->zstream);
177  if (zret != Z_OK) {
178  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
179  return 1;
180  }
181 
182  return 0;
183 }
184 
185 
186 
187 /*
188  *
189  * Uninit tscc decoder
190  *
191  */
193 {
194  CamtasiaContext * const c = avctx->priv_data;
195 
196  av_freep(&c->decomp_buf);
197 
198  if (c->pic.data[0])
199  avctx->release_buffer(avctx, &c->pic);
200  inflateEnd(&c->zstream);
201 
202  return 0;
203 }
204 
206  .name = "camtasia",
207  .type = AVMEDIA_TYPE_VIDEO,
208  .id = CODEC_ID_TSCC,
209  .priv_data_size = sizeof(CamtasiaContext),
210  .init = decode_init,
211  .close = decode_end,
212  .decode = decode_frame,
213  .capabilities = CODEC_CAP_DR1,
214  .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
215 };
216 
int height
Definition: tscc.c:62
int(* get_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called at the beginning of each frame to get a buffer for it.
Definition: avcodec.h:1726
enum PixelFormat pix_fmt
Pixel format, see PIX_FMT_xxx.
Definition: avcodec.h:1426
#define FF_BUFFER_HINTS_VALID
Definition: avcodec.h:880
Audio Video Frame.
Definition: avcodec.h:985
int bpp
Definition: tscc.c:56
int buffer_hints
codec suggestion on buffer type if != 0
Definition: avcodec.h:1195
AVCodecContext * avctx
Definition: tscc.c:52
void(* release_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called to release buffers which were allocated with get_buffer.
Definition: avcodec.h:1737
int size
Definition: avcodec.h:909
unsigned char * decomp_buf
Definition: tscc.c:60
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:138
four components are given, that's all.
Definition: avcodec.h:3367
AVCodec.
Definition: avcodec.h:3189
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:147
unsigned int decomp_size
Definition: tscc.c:58
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:228
z_stream zstream
Definition: tscc.c:63
#define av_cold
Definition: attributes.h:71
AVFrame pic
Definition: tscc.c:53
#define PIX_FMT_RGB555
Definition: pixfmt.h:177
static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
Definition: tscc.c:73
static av_cold int decode_init(AVCodecContext *avctx)
Definition: tscc.c:140
const char data[16]
Definition: mxf.c:60
uint8_t * data
Definition: avcodec.h:908
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1974
GetByteContext gb
Definition: tscc.c:61
static int init(AVCodecParserContext *s)
Definition: h264_parser.c:336
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:719
int reference
is this picture used as reference The values for this are the same as the MpegEncContext.picture_structure variable, that is 1->top field, 2->bottom field, 3->frame/both fields.
Definition: avcodec.h:1074
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:191
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:140
const char * name
Name of the codec implementation.
Definition: avcodec.h:3196
AVCodec ff_tscc_decoder
Definition: tscc.c:205
int width
picture width / height.
Definition: avcodec.h:1408
struct AVFrame AVFrame
Audio Video Frame.
struct TsccContext CamtasiaContext
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:185
NULL
Definition: eval.c:50
external API header
main external API structure.
Definition: avcodec.h:1329
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:327
uint32_t pal[256]
Definition: tscc.c:65
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:111
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:64
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: avcodec.h:1188
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:67
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: avcodec.h:997
#define AVPALETTE_SIZE
Definition: avcodec.h:3372
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:75
void * priv_data
Definition: avcodec.h:1531
int ff_msrle_decode(AVCodecContext *avctx, AVPicture *pic, int depth, GetByteContext *gb)
Decode stream in MS RLE format into frame.
Definition: msrledec.c:246
static av_cold int decode_end(AVCodecContext *avctx)
Definition: tscc.c:192
#define PIX_FMT_RGB32
Definition: pixfmt.h:169
int len