Libav
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 
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 
49 
50  // Bits per pixel
51  int bpp;
52  // Decompressed data size
53  unsigned int decomp_size;
54  // Decompression buffer
55  unsigned char* decomp_buf;
57  int height;
58  z_stream zstream;
59 
60  uint32_t pal[256];
62 
63 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
64  AVPacket *avpkt)
65 {
66  const uint8_t *buf = avpkt->data;
67  int buf_size = avpkt->size;
68  CamtasiaContext * const c = avctx->priv_data;
69  AVFrame *frame = data;
70  int ret;
71 
72  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0){
73  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
74  return ret;
75  }
76 
77  ret = inflateReset(&c->zstream);
78  if (ret != Z_OK) {
79  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
80  return AVERROR_UNKNOWN;
81  }
82  c->zstream.next_in = buf;
83  c->zstream.avail_in = buf_size;
84  c->zstream.next_out = c->decomp_buf;
85  c->zstream.avail_out = c->decomp_size;
86  ret = inflate(&c->zstream, Z_FINISH);
87  // Z_DATA_ERROR means empty picture
88  if ((ret != Z_OK) && (ret != Z_STREAM_END) && (ret != Z_DATA_ERROR)) {
89  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
90  return AVERROR_UNKNOWN;
91  }
92 
93 
94  if (ret != Z_DATA_ERROR) {
96  c->decomp_size - c->zstream.avail_out);
97  ff_msrle_decode(avctx, frame, c->bpp, &c->gb);
98  }
99 
100  /* make the palette available on the way out */
101  if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
103 
104  if (pal) {
105  frame->palette_has_changed = 1;
106  memcpy(c->pal, pal, AVPALETTE_SIZE);
107  }
108  memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
109  }
110 
111  *got_frame = 1;
112 
113  /* always report that the buffer was completely consumed */
114  return buf_size;
115 }
116 
118 {
119  CamtasiaContext * const c = avctx->priv_data;
120  int zret; // Zlib return code
121 
122  c->avctx = avctx;
123 
124  c->height = avctx->height;
125 
126  // Needed if zlib unused or init aborted before inflateInit
127  memset(&c->zstream, 0, sizeof(z_stream));
128  switch(avctx->bits_per_coded_sample){
129  case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
130  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
131  case 24:
132  avctx->pix_fmt = AV_PIX_FMT_BGR24;
133  break;
134  case 32: avctx->pix_fmt = AV_PIX_FMT_RGB32; break;
135  default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
136  return AVERROR_INVALIDDATA;
137  }
138  c->bpp = avctx->bits_per_coded_sample;
139  // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
140  c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
141 
142  /* Allocate decompression buffer */
143  if (c->decomp_size) {
144  if (!(c->decomp_buf = av_malloc(c->decomp_size))) {
145  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
146  return AVERROR(ENOMEM);
147  }
148  }
149 
150  c->zstream.zalloc = Z_NULL;
151  c->zstream.zfree = Z_NULL;
152  c->zstream.opaque = Z_NULL;
153  zret = inflateInit(&c->zstream);
154  if (zret != Z_OK) {
155  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
156  return AVERROR_UNKNOWN;
157  }
158 
159  return 0;
160 }
161 
163 {
164  CamtasiaContext * const c = avctx->priv_data;
165 
166  av_freep(&c->decomp_buf);
167 
168  inflateEnd(&c->zstream);
169 
170  return 0;
171 }
172 
174  .name = "camtasia",
175  .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
176  .type = AVMEDIA_TYPE_VIDEO,
177  .id = AV_CODEC_ID_TSCC,
178  .priv_data_size = sizeof(CamtasiaContext),
179  .init = decode_init,
180  .close = decode_end,
181  .decode = decode_frame,
182  .capabilities = AV_CODEC_CAP_DR1,
183 };
#define AVPALETTE_SIZE
Definition: avcodec.h:3402
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:62
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:140
int ff_msrle_decode(AVCodecContext *avctx, AVFrame *pic, int depth, GetByteContext *gb)
Decode stream in MS RLE format into frame.
Definition: msrledec.c:246
int size
Definition: avcodec.h:1347
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1621
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:132
unsigned char * decomp_buf
Definition: tscc.c:55
AVCodec.
Definition: avcodec.h:3120
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:202
z_stream zstream
Definition: tscc.c:58
uint8_t
#define av_cold
Definition: attributes.h:66
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:70
static av_cold int decode_init(AVCodecContext *avctx)
Definition: tscc.c:117
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:1346
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2769
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:148
const char * name
Name of the codec implementation.
Definition: avcodec.h:3127
AVCodecContext * avctx
Definition: tscc.c:48
GetByteContext gb
Definition: tscc.c:56
AVCodec ff_tscc_decoder
Definition: tscc.c:173
int width
picture width / height.
Definition: avcodec.h:1580
static int decode(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *pkt)
Definition: avconv.c:1288
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:62
if(ac->has_optimized_func)
NULL
Definition: eval.c:55
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1409
#define AV_PIX_FMT_RGB32
Definition: pixfmt.h:242
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:589
uint32_t pal[256]
Definition: tscc.c:60
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:273
unsigned int decomp_size
Definition: tscc.c:53
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
common internal api header.
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:251
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:61
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:582
void * priv_data
Definition: avcodec.h:1451
static av_cold int decode_end(AVCodecContext *avctx)
Definition: tscc.c:162
int height
Definition: tscc.c:57
uint8_t * av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int *size)
Get side information from packet.
Definition: avpacket.c:284
This structure stores compressed data.
Definition: avcodec.h:1323
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:838
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: tscc.c:63