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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 "libavcodec/h264.h"
24 #include "avformat.h"
25 #include "avio.h"
26 #include "avc.h"
27 
28 static const uint8_t *ff_avc_find_startcode_internal(const uint8_t *p, const uint8_t *end)
29 {
30  const uint8_t *a = p + 4 - ((intptr_t)p & 3);
31 
32  for (end -= 3; p < a && p < end; p++) {
33  if (p[0] == 0 && p[1] == 0 && p[2] == 1)
34  return p;
35  }
36 
37  for (end -= 3; p < end; p += 4) {
38  uint32_t x = *(const uint32_t*)p;
39 // if ((x - 0x01000100) & (~x) & 0x80008000) // little endian
40 // if ((x - 0x00010001) & (~x) & 0x00800080) // big endian
41  if ((x - 0x01010101) & (~x) & 0x80808080) { // generic
42  if (p[1] == 0) {
43  if (p[0] == 0 && p[2] == 1)
44  return p;
45  if (p[2] == 0 && p[3] == 1)
46  return p+1;
47  }
48  if (p[3] == 0) {
49  if (p[2] == 0 && p[4] == 1)
50  return p+2;
51  if (p[4] == 0 && p[5] == 1)
52  return p+3;
53  }
54  }
55  }
56 
57  for (end += 3; p < end; p++) {
58  if (p[0] == 0 && p[1] == 0 && p[2] == 1)
59  return p;
60  }
61 
62  return end + 3;
63 }
64 
65 const uint8_t *ff_avc_find_startcode(const uint8_t *p, const uint8_t *end){
67  if(p<out && out<end && !out[-1]) out--;
68  return out;
69 }
70 
71 int ff_avc_parse_nal_units(AVIOContext *pb, const uint8_t *buf_in, int size)
72 {
73  const uint8_t *p = buf_in;
74  const uint8_t *end = p + size;
75  const uint8_t *nal_start, *nal_end;
76 
77  size = 0;
78  nal_start = ff_avc_find_startcode(p, end);
79  for (;;) {
80  while (nal_start < end && !*(nal_start++));
81  if (nal_start == end)
82  break;
83 
84  nal_end = ff_avc_find_startcode(nal_start, end);
85  avio_wb32(pb, nal_end - nal_start);
86  avio_write(pb, nal_start, nal_end - nal_start);
87  size += 4 + nal_end - nal_start;
88  nal_start = nal_end;
89  }
90  return size;
91 }
92 
93 int ff_avc_parse_nal_units_buf(const uint8_t *buf_in, uint8_t **buf, int *size)
94 {
95  AVIOContext *pb;
96  int ret = avio_open_dyn_buf(&pb);
97  if(ret < 0)
98  return ret;
99 
100  ff_avc_parse_nal_units(pb, buf_in, *size);
101 
102  av_freep(buf);
103  *size = avio_close_dyn_buf(pb, buf);
104  return 0;
105 }
106 
108 {
109  AVIOContext *sps_pb = NULL, *pps_pb = NULL;
110  uint8_t *buf = NULL, *end, *start = NULL;
111  uint8_t *sps = NULL, *pps = NULL;
112  uint32_t sps_size = 0, pps_size = 0;
113  int ret, nb_sps = 0, nb_pps = 0;
114 
115  if (len <= 6)
116  return AVERROR_INVALIDDATA;
117 
118  /* check for H.264 start code */
119  if (AV_RB32(data) != 0x00000001 &&
120  AV_RB24(data) != 0x000001) {
121  avio_write(pb, data, len);
122  return 0;
123  }
124 
125  ret = ff_avc_parse_nal_units_buf(data, &buf, &len);
126  if (ret < 0)
127  return ret;
128  start = buf;
129  end = buf + len;
130 
131  ret = avio_open_dyn_buf(&sps_pb);
132  if (ret < 0)
133  goto fail;
134  ret = avio_open_dyn_buf(&pps_pb);
135  if (ret < 0)
136  goto fail;
137 
138  /* look for sps and pps */
139  while (end - buf > 4) {
140  uint32_t size;
141  uint8_t nal_type;
142  size = FFMIN(AV_RB32(buf), end - buf - 4);
143  buf += 4;
144  nal_type = buf[0] & 0x1f;
145 
146  if (nal_type == 7) { /* SPS */
147  nb_sps++;
148  if (size > UINT16_MAX || nb_sps >= H264_MAX_SPS_COUNT) {
149  ret = AVERROR_INVALIDDATA;
150  goto fail;
151  }
152  avio_wb16(sps_pb, size);
153  avio_write(sps_pb, buf, size);
154  } else if (nal_type == 8) { /* PPS */
155  nb_pps++;
156  if (size > UINT16_MAX || nb_pps >= H264_MAX_PPS_COUNT) {
157  ret = AVERROR_INVALIDDATA;
158  goto fail;
159  }
160  avio_wb16(pps_pb, size);
161  avio_write(pps_pb, buf, size);
162  }
163 
164  buf += size;
165  }
166  sps_size = avio_close_dyn_buf(sps_pb, &sps);
167  pps_size = avio_close_dyn_buf(pps_pb, &pps);
168 
169  if (sps_size < 6 || !pps_size) {
170  ret = AVERROR_INVALIDDATA;
171  goto fail;
172  }
173 
174  avio_w8(pb, 1); /* version */
175  avio_w8(pb, sps[3]); /* profile */
176  avio_w8(pb, sps[4]); /* profile compat */
177  avio_w8(pb, sps[5]); /* level */
178  avio_w8(pb, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 1 (11) */
179  avio_w8(pb, 0xe0 | nb_sps); /* 3 bits reserved (111) + 5 bits number of sps */
180 
181  avio_write(pb, sps, sps_size);
182  avio_w8(pb, nb_pps); /* number of pps */
183  avio_write(pb, pps, pps_size);
184 
185 fail:
186  if (!sps)
187  avio_close_dyn_buf(sps_pb, &sps);
188  if (!pps)
189  avio_close_dyn_buf(pps_pb, &pps);
190  av_free(sps);
191  av_free(pps);
192  av_free(start);
193 
194  return ret;
195 }
196 
198 {
199  uint16_t sps_size, pps_size;
200  uint8_t *out;
201  int out_size;
202 
203  *buf = NULL;
204  if (*size >= 4 && (AV_RB32(in) == 0x00000001 || AV_RB24(in) == 0x000001))
205  return 0;
206  if (*size < 11 || in[0] != 1)
207  return AVERROR_INVALIDDATA;
208 
209  sps_size = AV_RB16(&in[6]);
210  if (11 + sps_size > *size)
211  return AVERROR_INVALIDDATA;
212  pps_size = AV_RB16(&in[9 + sps_size]);
213  if (11 + sps_size + pps_size > *size)
214  return AVERROR_INVALIDDATA;
215  out_size = 8 + sps_size + pps_size;
216  out = av_mallocz(out_size + AV_INPUT_BUFFER_PADDING_SIZE);
217  if (!out)
218  return AVERROR(ENOMEM);
219  AV_WB32(&out[0], 0x00000001);
220  memcpy(out + 4, &in[8], sps_size);
221  AV_WB32(&out[4 + sps_size], 0x00000001);
222  memcpy(out + 8 + sps_size, &in[11 + sps_size], pps_size);
223  *buf = out;
224  *size = out_size;
225  return 0;
226 }
227 
229  const uint8_t *end,
230  int nal_length_size)
231 {
232  unsigned int res = 0;
233 
234  if (end - start < nal_length_size)
235  return NULL;
236  while (nal_length_size--)
237  res = (res << 8) | *start++;
238 
239  if (res > end - start)
240  return NULL;
241 
242  return start + res;
243 }
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#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:65
int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
Return the written size and a pointer to the buffer.
Definition: aviobuf.c:1364
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:236
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:1335
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:197
ptrdiff_t size
Definition: opengl_enc.c:101
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:216
H.264 common definitions.
#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:93
#define fail()
Definition: checkasm.h:113
int ff_avc_parse_nal_units(AVIOContext *pb, const uint8_t *buf_in, int size)
Definition: avc.c:71
#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:28
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:194
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
static int FUNC() pps(CodedBitstreamContext *ctx, RWContext *rw, H264RawPPS *current)
#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:228
static int FUNC() sps(CodedBitstreamContext *ctx, RWContext *rw, H264RawSPS *current)
void avio_wb16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:473
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:770
#define av_free(p)
int len
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:375
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:107