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dnxhd_parser.c
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1 /*
2  * DNxHD/VC-3 parser
3  * Copyright (c) 2008 Baptiste Coudurier <baptiste.coudurier@free.fr>
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  * DNxHD/VC-3 parser
25  */
26 
27 #include "parser.h"
28 #include "dnxhddata.h"
29 
30 typedef struct {
33  int cur_field; /* first field is 0, second is 1 */
34  int cur_byte;
35  int remaining;
36  int w, h;
38 
39 static int dnxhd_get_hr_frame_size(int cid, int w, int h)
40 {
41  int result, i = ff_dnxhd_get_cid_table(cid);
42 
43  if (i < 0)
44  return i;
45 
46  result = ((h + 15) / 16) * ((w + 15) / 16) * ff_dnxhd_cid_table[i].packet_scale.num / ff_dnxhd_cid_table[i].packet_scale.den;
47  result = (result + 2048) / 4096 * 4096;
48 
49  return FFMAX(result, 8192);
50 }
51 
53  const uint8_t *buf, int buf_size)
54 {
55  ParseContext *pc = &dctx->pc;
56  uint64_t state = pc->state64;
57  int pic_found = pc->frame_start_found;
58  int i = 0;
59  int interlaced = dctx->interlaced;
60  int cur_field = dctx->cur_field;
61 
62  if (!pic_found) {
63  for (i = 0; i < buf_size; i++) {
64  state = (state << 8) | buf[i];
65  if (ff_dnxhd_check_header_prefix(state & 0xffffffffff00LL) != 0) {
66  i++;
67  pic_found = 1;
68  interlaced = (state&2)>>1; /* byte following the 5-byte header prefix */
69  cur_field = state&1;
70  dctx->cur_byte = 0;
71  dctx->remaining = 0;
72  break;
73  }
74  }
75  }
76 
77  if (pic_found && !dctx->remaining) {
78  if (!buf_size) /* EOF considered as end of frame */
79  return 0;
80  for (; i < buf_size; i++) {
81  dctx->cur_byte++;
82  state = (state << 8) | buf[i];
83 
84  if (dctx->cur_byte == 24) {
85  dctx->h = (state >> 32) & 0xFFFF;
86  } else if (dctx->cur_byte == 26) {
87  dctx->w = (state >> 32) & 0xFFFF;
88  } else if (dctx->cur_byte == 42) {
89  int cid = (state >> 32) & 0xFFFFFFFF;
90 
91  if (cid <= 0)
92  continue;
93 
95  if (dctx->remaining <= 0) {
96  dctx->remaining = dnxhd_get_hr_frame_size(cid, dctx->w, dctx->h);
97  if (dctx->remaining <= 0)
98  return dctx->remaining;
99  }
100  if (buf_size - i >= dctx->remaining && (!dctx->interlaced || dctx->cur_field)) {
101  int remaining = dctx->remaining;
102 
103  pc->frame_start_found = 0;
104  pc->state64 = -1;
105  dctx->interlaced = interlaced;
106  dctx->cur_field = 0;
107  dctx->cur_byte = 0;
108  dctx->remaining = 0;
109  return remaining;
110  } else {
111  dctx->remaining -= buf_size;
112  }
113  }
114  }
115  } else if (pic_found) {
116  if (dctx->remaining > buf_size) {
117  dctx->remaining -= buf_size;
118  } else {
119  int remaining = dctx->remaining;
120 
121  pc->frame_start_found = 0;
122  pc->state64 = -1;
123  dctx->interlaced = interlaced;
124  dctx->cur_field = 0;
125  dctx->cur_byte = 0;
126  dctx->remaining = 0;
127  return remaining;
128  }
129  }
130  pc->frame_start_found = pic_found;
131  pc->state64 = state;
132  dctx->interlaced = interlaced;
133  dctx->cur_field = cur_field;
134  return END_NOT_FOUND;
135 }
136 
138  AVCodecContext *avctx,
139  const uint8_t **poutbuf, int *poutbuf_size,
140  const uint8_t *buf, int buf_size)
141 {
142  DNXHDParserContext *dctx = s->priv_data;
143  ParseContext *pc = &dctx->pc;
144  int next;
145 
147  next = buf_size;
148  } else {
149  next = dnxhd_find_frame_end(dctx, buf, buf_size);
150  if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
151  *poutbuf = NULL;
152  *poutbuf_size = 0;
153  return buf_size;
154  }
155  }
156  *poutbuf = buf;
157  *poutbuf_size = buf_size;
158  return next;
159 }
160 
163  .priv_data_size = sizeof(DNXHDParserContext),
164  .parser_parse = dnxhd_parse,
165  .parser_close = ff_parse_close,
166 };
#define NULL
Definition: coverity.c:32
static av_always_inline uint64_t ff_dnxhd_check_header_prefix(uint64_t prefix)
Definition: dnxhddata.h:78
const char * s
Definition: avisynth_c.h:768
int num
Numerator.
Definition: rational.h:59
const CIDEntry ff_dnxhd_cid_table[]
Definition: dnxhddata.c:935
int codec_ids[5]
Definition: avcodec.h:5233
static struct @257 state
int frame_start_found
Definition: parser.h:34
uint8_t
static int dnxhd_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: dnxhd_parser.c:137
static int dnxhd_get_hr_frame_size(int cid, int w, int h)
Definition: dnxhd_parser.c:39
int avpriv_dnxhd_get_frame_size(int cid)
Definition: dnxhddata.c:1099
int ff_dnxhd_get_cid_table(int cid)
Definition: dnxhddata.c:1090
AVRational packet_scale
Definition: dnxhddata.h:59
int ff_combine_frame(ParseContext *pc, int next, const uint8_t **buf, int *buf_size)
Combine the (truncated) bitstream to a complete frame.
Definition: parser.c:250
AVCodecParser ff_dnxhd_parser
Definition: dnxhd_parser.c:161
#define FFMAX(a, b)
Definition: common.h:94
void ff_parse_close(AVCodecParserContext *s)
Definition: parser.c:326
static int dnxhd_find_frame_end(DNXHDParserContext *dctx, const uint8_t *buf, int buf_size)
Definition: dnxhd_parser.c:52
uint8_t interlaced
Definition: mxfenc.c:1822
ParseContext pc
Definition: dnxhd_parser.c:31
main external API structure.
Definition: avcodec.h:1722
void * buf
Definition: avisynth_c.h:690
uint64_t state64
contains the last 8 bytes in MSB order
Definition: parser.h:37
#define END_NOT_FOUND
Definition: parser.h:40
#define PARSER_FLAG_COMPLETE_FRAMES
Definition: avcodec.h:5099
int den
Denominator.
Definition: rational.h:60