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avc.c
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1 /*
2  * AVC helper functions for muxers
3  * Copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@smartjog.com>
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 #include "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 #include "avio.h"
25 #include "avc.h"
26 
27 static const uint8_t *ff_avc_find_startcode_internal(const uint8_t *p, const uint8_t *end)
28 {
29  const uint8_t *a = p + 4 - ((intptr_t)p & 3);
30 
31  for (end -= 3; p < a && p < end; p++) {
32  if (p[0] == 0 && p[1] == 0 && p[2] == 1)
33  return p;
34  }
35 
36  for (end -= 3; p < end; p += 4) {
37  uint32_t x = *(const uint32_t*)p;
38 // if ((x - 0x01000100) & (~x) & 0x80008000) // little endian
39 // if ((x - 0x00010001) & (~x) & 0x00800080) // big endian
40  if ((x - 0x01010101) & (~x) & 0x80808080) { // generic
41  if (p[1] == 0) {
42  if (p[0] == 0 && p[2] == 1)
43  return p;
44  if (p[2] == 0 && p[3] == 1)
45  return p+1;
46  }
47  if (p[3] == 0) {
48  if (p[2] == 0 && p[4] == 1)
49  return p+2;
50  if (p[4] == 0 && p[5] == 1)
51  return p+3;
52  }
53  }
54  }
55 
56  for (end += 3; p < end; p++) {
57  if (p[0] == 0 && p[1] == 0 && p[2] == 1)
58  return p;
59  }
60 
61  return end + 3;
62 }
63 
64 const uint8_t *ff_avc_find_startcode(const uint8_t *p, const uint8_t *end){
66  if(p<out && out<end && !out[-1]) out--;
67  return out;
68 }
69 
70 int ff_avc_parse_nal_units(AVIOContext *pb, const uint8_t *buf_in, int size)
71 {
72  const uint8_t *p = buf_in;
73  const uint8_t *end = p + size;
74  const uint8_t *nal_start, *nal_end;
75 
76  size = 0;
77  nal_start = ff_avc_find_startcode(p, end);
78  for (;;) {
79  while (nal_start < end && !*(nal_start++));
80  if (nal_start == end)
81  break;
82 
83  nal_end = ff_avc_find_startcode(nal_start, end);
84  avio_wb32(pb, nal_end - nal_start);
85  avio_write(pb, nal_start, nal_end - nal_start);
86  size += 4 + nal_end - nal_start;
87  nal_start = nal_end;
88  }
89  return size;
90 }
91 
92 int ff_avc_parse_nal_units_buf(const uint8_t *buf_in, uint8_t **buf, int *size)
93 {
94  AVIOContext *pb;
95  int ret = avio_open_dyn_buf(&pb);
96  if(ret < 0)
97  return ret;
98 
99  ff_avc_parse_nal_units(pb, buf_in, *size);
100 
101  av_freep(buf);
102  *size = avio_close_dyn_buf(pb, buf);
103  return 0;
104 }
105 
107 {
108  if (len > 6) {
109  /* check for H.264 start code */
110  if (AV_RB32(data) == 0x00000001 ||
111  AV_RB24(data) == 0x000001) {
112  uint8_t *buf=NULL, *end, *start;
113  uint32_t sps_size=0, pps_size=0;
114  uint8_t *sps=0, *pps=0;
115 
116  int ret = ff_avc_parse_nal_units_buf(data, &buf, &len);
117  if (ret < 0)
118  return ret;
119  start = buf;
120  end = buf + len;
121 
122  /* look for sps and pps */
123  while (end - buf > 4) {
124  uint32_t size;
125  uint8_t nal_type;
126  size = FFMIN(AV_RB32(buf), end - buf - 4);
127  buf += 4;
128  nal_type = buf[0] & 0x1f;
129 
130  if (nal_type == 7) { /* SPS */
131  sps = buf;
132  sps_size = size;
133  } else if (nal_type == 8) { /* PPS */
134  pps = buf;
135  pps_size = size;
136  }
137 
138  buf += size;
139  }
140 
141  if (!sps || !pps || sps_size < 4 || sps_size > UINT16_MAX || pps_size > UINT16_MAX)
142  return AVERROR_INVALIDDATA;
143 
144  avio_w8(pb, 1); /* version */
145  avio_w8(pb, sps[1]); /* profile */
146  avio_w8(pb, sps[2]); /* profile compat */
147  avio_w8(pb, sps[3]); /* level */
148  avio_w8(pb, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 1 (11) */
149  avio_w8(pb, 0xe1); /* 3 bits reserved (111) + 5 bits number of sps (00001) */
150 
151  avio_wb16(pb, sps_size);
152  avio_write(pb, sps, sps_size);
153  avio_w8(pb, 1); /* number of pps */
154  avio_wb16(pb, pps_size);
155  avio_write(pb, pps, pps_size);
156  av_free(start);
157  } else {
158  avio_write(pb, data, len);
159  }
160  }
161  return 0;
162 }
163 
165 {
166  uint16_t sps_size, pps_size;
167  uint8_t *out;
168  int out_size;
169 
170  *buf = NULL;
171  if (*size >= 4 && (AV_RB32(in) == 0x00000001 || AV_RB24(in) == 0x000001))
172  return 0;
173  if (*size < 11 || in[0] != 1)
174  return AVERROR_INVALIDDATA;
175 
176  sps_size = AV_RB16(&in[6]);
177  if (11 + sps_size > *size)
178  return AVERROR_INVALIDDATA;
179  pps_size = AV_RB16(&in[9 + sps_size]);
180  if (11 + sps_size + pps_size > *size)
181  return AVERROR_INVALIDDATA;
182  out_size = 8 + sps_size + pps_size;
183  out = av_mallocz(out_size + AV_INPUT_BUFFER_PADDING_SIZE);
184  if (!out)
185  return AVERROR(ENOMEM);
186  AV_WB32(&out[0], 0x00000001);
187  memcpy(out + 4, &in[8], sps_size);
188  AV_WB32(&out[4 + sps_size], 0x00000001);
189  memcpy(out + 8 + sps_size, &in[11 + sps_size], pps_size);
190  *buf = out;
191  *size = out_size;
192  return 0;
193 }
194 
196  const uint8_t *end,
197  int nal_length_size)
198 {
199  unsigned int res = 0;
200 
201  if (end - start < nal_length_size)
202  return NULL;
203  while (nal_length_size--)
204  res = (res << 8) | *start++;
205 
206  if (res > end - start)
207  return NULL;
208 
209  return start + res;
210 }
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:147
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
Buffered I/O operations.
const uint8_t * ff_avc_find_startcode(const uint8_t *p, const uint8_t *end)
Definition: avc.c:64
int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
Return the written size and a pointer to the buffer.
Definition: aviobuf.c:1278
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
int out_size
Definition: movenc.c:55
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:252
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
int avio_open_dyn_buf(AVIOContext **s)
Open a write only memory stream.
Definition: aviobuf.c:1266
uint8_t
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:87
int ff_avc_write_annexb_extradata(const uint8_t *in, uint8_t **buf, int *size)
Definition: avc.c:164
ptrdiff_t size
Definition: opengl_enc.c:101
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:204
#define AVERROR(e)
Definition: error.h:43
int ff_avc_parse_nal_units_buf(const uint8_t *buf_in, uint8_t **buf, int *size)
Definition: avc.c:92
int ff_avc_parse_nal_units(AVIOContext *pb, const uint8_t *buf_in, int size)
Definition: avc.c:70
#define FFMIN(a, b)
Definition: common.h:96
static const uint8_t * ff_avc_find_startcode_internal(const uint8_t *p, const uint8_t *end)
Definition: avc.c:27
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:87
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:182
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
void * buf
Definition: avisynth_c.h:690
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
const uint8_t * ff_avc_mp4_find_startcode(const uint8_t *start, const uint8_t *end, int nal_length_size)
Definition: avc.c:195
void avio_wb16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:452
Main libavformat public API header.
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:733
#define av_free(p)
int len
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:354
FILE * out
Definition: movenc.c:54
#define av_freep(p)
void INT64 start
Definition: avisynth_c.h:690
int ff_isom_write_avcc(AVIOContext *pb, const uint8_t *data, int len)
Definition: avc.c:106