FFmpeg: libavcodec/truemotion2rt.c Source File

FFmpeg
truemotion2rt.c
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1 /*
2  * Duck TrueMotion 2.0 Real Time decoder
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/internal.h"
22 #include "libavutil/intreadwrite.h"
23 
24  #define BITSTREAM_READER_LE
25 #include "avcodec.h"
26 #include "codec_internal.h"
27 #include "decode.h"
28 #include "get_bits.h"
29 
30  typedef struct TrueMotion2RTContext {
31   GetBitContext gb;
32   int delta_size;
33   int hscale;
34 } TrueMotion2RTContext;
35 
36  static const int16_t delta_tab2[] = {
37  5, -7, 36, -36,
38 };
39 
40  static const int16_t delta_tab3[] = {
41  2, -3, 8, -8, 18, -18, 36, -36,
42 };
43 
44  static const int16_t delta_tab4[] = {
45  1, -1, 2, -3, 8, -8, 18, -18, 36, -36, 54, -54, 96, -96, 144, -144,
46 };
47 
48  static const int16_t *const delta_tabs[] = {
49  delta_tab2, delta_tab3, delta_tab4,
50 };
51 
52 /* Returns the number of bytes consumed from the bytestream, or
53  * AVERROR_INVALIDDATA if there was an error while decoding the header. */
54  static int truemotion2rt_decode_header(AVCodecContext *avctx, const AVPacket *avpkt)
55 {
56  TrueMotion2RTContext *s = avctx->priv_data;
57  int header_size;
58  uint8_t header_buffer[128] = { 0 }; /* logical maximum header size */
59  const uint8_t *buf = avpkt->data;
60  int size = avpkt->size;
61  int width, height;
62  int ret, i;
63 
64  if (size < 1) {
65  av_log(avctx, AV_LOG_ERROR, "input packet too small (%d)\n", size);
66  return AVERROR_INVALIDDATA;
67  }
68 
69  header_size = ((buf[0] >> 5) | (buf[0] << 3)) & 0x7f;
70  if (header_size < 10) {
71  av_log(avctx, AV_LOG_ERROR, "invalid header size (%d)\n", header_size);
72  return AVERROR_INVALIDDATA;
73  }
74 
75  if (header_size + 1 > size) {
76  av_log(avctx, AV_LOG_ERROR, "input packet too small (%d)\n", size);
77  return AVERROR_INVALIDDATA;
78  }
79 
80  /* unscramble the header bytes with a XOR operation */
81  for (i = 1; i < header_size; i++)
82  header_buffer[i - 1] = buf[i] ^ buf[i + 1];
83 
84  s->delta_size = header_buffer[1];
85  s->hscale = 1 + !!header_buffer[3];
86  if (s->delta_size < 2 || s->delta_size > 4)
87  return AVERROR_INVALIDDATA;
88 
89  height = AV_RL16(header_buffer + 5);
90  width = AV_RL16(header_buffer + 7);
91 
92  ret = ff_set_dimensions(avctx, width, height);
93  if (ret < 0)
94  return ret;
95 
96  av_log(avctx, AV_LOG_DEBUG, "Header size: %d\n", header_size);
97  return header_size;
98 }
99 
100  static int truemotion2rt_decode_frame(AVCodecContext *avctx, AVFrame *p,
101  int *got_frame, AVPacket *avpkt)
102 {
103  TrueMotion2RTContext *s = avctx->priv_data;
104  GetBitContext *gb = &s->gb;
105  uint8_t *dst;
106  int x, y, delta_mode;
107  int ret;
108 
109  ret = truemotion2rt_decode_header(avctx, avpkt);
110  if (ret < 0)
111  return ret;
112 
113  if ((avctx->width + s->hscale - 1)/ s->hscale * avctx->height * s->delta_size > avpkt->size * 8LL * 4)
114  return AVERROR_INVALIDDATA;
115 
116  ret = init_get_bits8(gb, avpkt->data + ret, avpkt->size - ret);
117  if (ret < 0)
118  return ret;
119 
120  ret = ff_get_buffer(avctx, p, 0);
121  if (ret < 0)
122  return ret;
123 
124  skip_bits(gb, 32);
125  delta_mode = s->delta_size - 2;
126  dst = p->data[0];
127  for (y = 0; y < avctx->height; y++) {
128  int diff = 0;
129  for (x = 0; x < avctx->width; x += s->hscale) {
130  diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
131  dst[x] = av_clip_uint8((y ? dst[x - p->linesize[0]] : 0) + diff);
132  }
133  dst += p->linesize[0];
134  }
135 
136  if (s->hscale > 1) {
137  dst = p->data[0];
138  for (y = 0; y < avctx->height; y++) {
139  for (x = 1; x < avctx->width; x += s->hscale)
140  dst[x] = dst[x - 1];
141  dst += p->linesize[0];
142  }
143  }
144 
145  dst = p->data[0];
146  for (y = 0; y < avctx->height; y++) {
147  for (x = 0; x < avctx->width; x++)
148  dst[x] = av_clip_uint8(dst[x] + (dst[x] - 128) / 3);
149  dst += p->linesize[0];
150  }
151 
152  dst = p->data[1];
153  for (y = 0; y < avctx->height >> 2; y++) {
154  int diff = 0;
155  for (x = 0; x < avctx->width >> 2; x += s->hscale) {
156  diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
157  dst[x] = av_clip_uint8((y ? dst[x - p->linesize[1]] : 128) + diff);
158  }
159  dst += p->linesize[1];
160  }
161 
162  if (s->hscale > 1) {
163  dst = p->data[1];
164  for (y = 0; y < avctx->height >> 2; y++) {
165  for (x = 1; x < avctx->width >> 2; x += s->hscale)
166  dst[x] = dst[x - 1];
167  dst += p->linesize[1];
168  }
169  }
170 
171  dst = p->data[1];
172  for (y = 0; y < avctx->height >> 2; y++) {
173  for (x = 0; x < avctx->width >> 2; x++)
174  dst[x] += (dst[x] - 128) / 8;
175  dst += p->linesize[1];
176  }
177 
178  dst = p->data[2];
179  for (y = 0; y < avctx->height >> 2; y++) {
180  int diff = 0;
181  for (x = 0; x < avctx->width >> 2; x += s->hscale) {
182  diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
183  dst[x] = av_clip_uint8((y ? dst[x - p->linesize[2]] : 128) + diff);
184  }
185  dst += p->linesize[2];
186  }
187 
188  if (s->hscale > 1) {
189  dst = p->data[2];
190  for (y = 0; y < avctx->height >> 2; y++) {
191  for (x = 1; x < avctx->width >> 2; x += s->hscale)
192  dst[x] = dst[x - 1];
193  dst += p->linesize[2];
194  }
195  }
196 
197  dst = p->data[2];
198  for (y = 0; y < avctx->height >> 2; y++) {
199  for (x = 0; x < avctx->width >> 2; x++)
200  dst[x] += (dst[x] - 128) / 8;
201  dst += p->linesize[2];
202  }
203 
204  *got_frame = 1;
205 
206  return avpkt->size;
207 }
208 
209  static av_cold int truemotion2rt_decode_init(AVCodecContext *avctx)
210 {
211  avctx->pix_fmt = AV_PIX_FMT_YUV410P;
212  return 0;
213 }
214 
215  const FFCodec ff_truemotion2rt_decoder = {
216  .p.name = "truemotion2rt",
217  CODEC_LONG_NAME("Duck TrueMotion 2.0 Real Time"),
218  .p.type = AVMEDIA_TYPE_VIDEO,
219  .p.id = AV_CODEC_ID_TRUEMOTION2RT,
220  .priv_data_size = sizeof(TrueMotion2RTContext),
221  .init = truemotion2rt_decode_init,
222  FF_CODEC_DECODE_CB(truemotion2rt_decode_frame),
223  .p.capabilities = AV_CODEC_CAP_DR1,
224 };
AV_CODEC_ID_TRUEMOTION2RT
@ AV_CODEC_ID_TRUEMOTION2RT
Definition: codec_id.h:268
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:389
AVPacket::data
uint8_t * data
Definition: packet.h:539
FFCodec
Definition: codec_internal.h:127
delta_tabs
static const int16_t *const delta_tabs[]
Definition: truemotion2rt.c:48
ff_set_dimensions
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:94
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:410
skip_bits
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:381
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:335
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
ff_truemotion2rt_decoder
const FFCodec ff_truemotion2rt_decoder
Definition: truemotion2rt.c:215
GetBitContext
Definition: get_bits.h:108
delta_tab2
static const int16_t delta_tab2[]
Definition: truemotion2rt.c:36
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
init_get_bits8
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:545
TrueMotion2RTContext::hscale
int hscale
Definition: truemotion2rt.c:33
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:311
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
decode.h
get_bits.h
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:94
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:296
delta_tab4
static const int16_t delta_tab4[]
Definition: truemotion2rt.c:44
TrueMotion2RTContext
Definition: truemotion2rt.c:30
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1719
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:368
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:540
height
#define height
Definition: dsp.h:85
codec_internal.h
dst
uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst
Definition: dsp.h:83
size
int size
Definition: twinvq_data.h:10344
diff
static av_always_inline int diff(const struct color_info *a, const struct color_info *b, const int trans_thresh)
Definition: vf_paletteuse.c:164
TrueMotion2RTContext::gb
GetBitContext gb
Definition: truemotion2rt.c:31
delta_tab3
static const int16_t delta_tab3[]
Definition: truemotion2rt.c:40
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
internal.h
truemotion2rt_decode_header
static int truemotion2rt_decode_header(AVCodecContext *avctx, const AVPacket *avpkt)
Definition: truemotion2rt.c:54
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
AVCodecContext::height
int height
Definition: avcodec.h:624
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:663
avcodec.h
ret
ret
Definition: filter_design.txt:187
TrueMotion2RTContext::delta_size
int delta_size
Definition: truemotion2rt.c:32
AVCodecContext
main external API structure.
Definition: avcodec.h:451
av_clip_uint8
#define av_clip_uint8
Definition: common.h:106
truemotion2rt_decode_frame
static int truemotion2rt_decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)
Definition: truemotion2rt.c:100
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:478
AVPacket
This structure stores compressed data.
Definition: packet.h:516
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:624
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:434
AV_PIX_FMT_YUV410P
@ AV_PIX_FMT_YUV410P
planar YUV 4:1:0, 9bpp, (1 Cr & Cb sample per 4x4 Y samples)
Definition: pixfmt.h:79
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
width
#define width
Definition: dsp.h:85
truemotion2rt_decode_init
static av_cold int truemotion2rt_decode_init(AVCodecContext *avctx)
Definition: truemotion2rt.c:209
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