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 
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;
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  int palette_has_changed = 0;
73 
74  if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
77 
78  if (pal && size == AVPALETTE_SIZE) {
79  palette_has_changed = 1;
80  memcpy(c->pal, pal, AVPALETTE_SIZE);
81  } else if (pal) {
82  av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
83  }
84  }
85 
86  ret = inflateReset(&c->zstream);
87  if (ret != Z_OK) {
88  av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
89  return AVERROR_UNKNOWN;
90  }
91  c->zstream.next_in = buf;
92  c->zstream.avail_in = buf_size;
93  c->zstream.next_out = c->decomp_buf;
94  c->zstream.avail_out = c->decomp_size;
95  ret = inflate(&c->zstream, Z_FINISH);
96  // Z_DATA_ERROR means empty picture
97  if (ret == Z_DATA_ERROR && !palette_has_changed) {
98  return buf_size;
99  }
100 
101  if ((ret != Z_OK) && (ret != Z_STREAM_END) && (ret != Z_DATA_ERROR)) {
102  av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
103  return AVERROR_UNKNOWN;
104  }
105 
106  if ((ret = ff_reget_buffer(avctx, frame, 0)) < 0)
107  return ret;
108 
109  if (ret != Z_DATA_ERROR) {
110  bytestream2_init(&c->gb, c->decomp_buf,
111  c->decomp_size - c->zstream.avail_out);
112  ff_msrle_decode(avctx, frame, c->bpp, &c->gb);
113  }
114 
115  /* make the palette available on the way out */
116  if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
117  frame->palette_has_changed = palette_has_changed;
118  memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
119  }
120 
121  if ((ret = av_frame_ref(data, frame)) < 0)
122  return ret;
123  *got_frame = 1;
124 
125  /* always report that the buffer was completely consumed */
126  return buf_size;
127 }
128 
130 {
131  CamtasiaContext * const c = avctx->priv_data;
132  int zret; // Zlib return code
133 
134  c->avctx = avctx;
135 
136  c->height = avctx->height;
137 
138  // Needed if zlib unused or init aborted before inflateInit
139  memset(&c->zstream, 0, sizeof(z_stream));
140  switch(avctx->bits_per_coded_sample){
141  case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
142  case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
143  case 24:
144  avctx->pix_fmt = AV_PIX_FMT_BGR24;
145  break;
146  case 32: avctx->pix_fmt = AV_PIX_FMT_0RGB32; break;
147  default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
148  return AVERROR_PATCHWELCOME;
149  }
150  c->bpp = avctx->bits_per_coded_sample;
151  // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
152  c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
153 
154  /* Allocate decompression buffer */
155  if (c->decomp_size) {
156  if (!(c->decomp_buf = av_malloc(c->decomp_size))) {
157  av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
158  return AVERROR(ENOMEM);
159  }
160  }
161 
162  c->zstream.zalloc = Z_NULL;
163  c->zstream.zfree = Z_NULL;
164  c->zstream.opaque = Z_NULL;
165  zret = inflateInit(&c->zstream);
166  if (zret != Z_OK) {
167  av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
168  return AVERROR_UNKNOWN;
169  }
170 
171  c->frame = av_frame_alloc();
172  if (!c->frame)
173  return AVERROR(ENOMEM);
174 
175  return 0;
176 }
177 
179 {
180  CamtasiaContext * const c = avctx->priv_data;
181 
182  av_freep(&c->decomp_buf);
183  av_frame_free(&c->frame);
184 
185  inflateEnd(&c->zstream);
186 
187  return 0;
188 }
189 
191  .name = "camtasia",
192  .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
193  .type = AVMEDIA_TYPE_VIDEO,
194  .id = AV_CODEC_ID_TSCC,
195  .priv_data_size = sizeof(CamtasiaContext),
196  .init = decode_init,
197  .close = decode_end,
198  .decode = decode_frame,
199  .capabilities = AV_CODEC_CAP_DR1,
200  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
201 };
AVCodec
AVCodec.
Definition: codec.h:197
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
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
av_packet_get_side_data
uint8_t * av_packet_get_side_data(const AVPacket *pkt, enum AVPacketSideDataType type, buffer_size_t *size)
Definition: avpacket.c:368
GetByteContext
Definition: bytestream.h:33
TsccContext::height
int height
Definition: tscc.c:58
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:369
AV_PKT_DATA_PALETTE
@ AV_PKT_DATA_PALETTE
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette.
Definition: packet.h:46
TsccContext::gb
GetByteContext gb
Definition: tscc.c:57
data
const char data[16]
Definition: mxf.c:142
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
TsccContext::frame
AVFrame * frame
Definition: tscc.c:49
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
TsccContext::decomp_size
unsigned int decomp_size
Definition: tscc.c:54
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: tscc.c:64
ff_tscc_decoder
AVCodec ff_tscc_decoder
Definition: tscc.c:190
inflate
static void inflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:198
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
av_cold
#define av_cold
Definition: attributes.h:90
TsccContext::zstream
z_stream zstream
Definition: tscc.c:59
TsccContext::avctx
AVCodecContext * avctx
Definition: tscc.c:48
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
buffer_size_t
int buffer_size_t
Definition: internal.h:306
if
if(ret)
Definition: filter_design.txt:179
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
msrledec.h
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
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:370
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:117
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:443
size
int size
Definition: twinvq_data.h:10344
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Definition: tscc.c:178
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1740
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: tscc.c:129
FF_CODEC_CAP_INIT_CLEANUP
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:49
AV_PIX_FMT_RGB555
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:387
uint8_t
uint8_t
Definition: audio_convert.c:194
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:204
AVCodecContext::height
int height
Definition: avcodec.h:709
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:746
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
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:2007
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AV_PIX_FMT_0RGB32
#define AV_PIX_FMT_0RGB32
Definition: pixfmt.h:376
TsccContext
Definition: tscc.c:46
AVCodecContext
main external API structure.
Definition: avcodec.h:536
TsccContext::pal
uint32_t pal[256]
Definition: tscc.c:61
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AV_CODEC_ID_TSCC
@ AV_CODEC_ID_TSCC
Definition: codec_id.h:105
TsccContext::bpp
int bpp
Definition: tscc.c:52
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
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:563
AVPacket
This structure stores compressed data.
Definition: packet.h:346
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:709
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:28
TsccContext::decomp_buf
unsigned char * decomp_buf
Definition: tscc.c:56