obs-studio/deps/libcaption/examples/flv.c

384 lines
12 KiB
C

/**********************************************************************************************/
/* The MIT License */
/* */
/* Copyright 2016-2016 Twitch Interactive, Inc. or its affiliates. All Rights Reserved. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining a copy */
/* of this software and associated documentation files (the "Software"), to deal */
/* in the Software without restriction, including without limitation the rights */
/* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell */
/* copies of the Software, and to permit persons to whom the Software is */
/* furnished to do so, subject to the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be included in */
/* all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR */
/* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, */
/* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE */
/* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER */
/* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, */
/* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN */
/* THE SOFTWARE. */
/**********************************************************************************************/
#include "flv.h"
#include <stdlib.h>
#include <string.h>
void flvtag_init (flvtag_t* tag)
{
memset (tag,0,sizeof (flvtag_t));
}
void flvtag_free (flvtag_t* tag)
{
if (tag->data) {
free (tag->data);
}
flvtag_init (tag);
}
int flvtag_reserve (flvtag_t* tag, uint32_t size)
{
size += FLV_TAG_HEADER_SIZE + FLV_TAG_FOOTER_SIZE;
if (size > tag->aloc) {
tag->data = realloc (tag->data,size);
tag->aloc = size;
}
return 1;
}
FILE* flv_open_read (const char* flv)
{
if (0 == flv || 0 == strcmp ("-",flv)) {
return stdin;
}
return fopen (flv,"rb");
}
FILE* flv_open_write (const char* flv)
{
if (0 == flv || 0 == strcmp ("-",flv)) {
return stdout;
}
return fopen (flv,"wb");
}
FILE* flv_close (FILE* flv)
{
fclose (flv);
return 0;
}
int flv_read_header (FILE* flv, int* has_audio, int* has_video)
{
uint8_t h[FLV_HEADER_SIZE];
if (FLV_HEADER_SIZE != fread (&h[0],1,FLV_HEADER_SIZE,flv)) {
return 0;
}
if ('F' != h[0] || 'L' != h[1] || 'V' != h[2]) {
return 0;
}
(*has_audio) = h[4]&0x04;
(*has_video) = h[4]&0x01;
return 1;
}
int flv_write_header (FILE* flv, int has_audio, int has_video)
{
uint8_t h[FLV_HEADER_SIZE] = {'F', 'L', 'V', 1, (has_audio?0x04:0x00) | (has_video?0x01:0x00), 0, 0, 0, 9, 0, 0, 0, 0 };
return FLV_HEADER_SIZE == fwrite (&h[0],1,FLV_HEADER_SIZE,flv);
}
int flv_read_tag (FILE* flv, flvtag_t* tag)
{
uint32_t size;
uint8_t h[FLV_TAG_HEADER_SIZE];
if (FLV_TAG_HEADER_SIZE != fread (&h[0],1,FLV_TAG_HEADER_SIZE,flv)) {
return 0;
}
size = ( (h[1]<<16) | (h[2]<<8) |h[3]);
flvtag_reserve (tag, size);
// copy header to buffer
memcpy (tag->data,&h[0],FLV_TAG_HEADER_SIZE);
if (size+FLV_TAG_FOOTER_SIZE != fread (&tag->data[FLV_TAG_HEADER_SIZE],1,size+FLV_TAG_FOOTER_SIZE,flv)) {
return 0;
}
return 1;
}
int flv_write_tag (FILE* flv, flvtag_t* tag)
{
size_t size = flvtag_raw_size (tag);
return size == fwrite (flvtag_raw_data (tag),1,size,flv);
}
////////////////////////////////////////////////////////////////////////////////
size_t flvtag_header_size (flvtag_t* tag)
{
switch (flvtag_type (tag)) {
case flvtag_type_audio:
return FLV_TAG_HEADER_SIZE + (flvtag_soundformat_aac != flvtag_soundformat (tag) ? 1 : 2);
case flvtag_type_video:
// CommandFrame does not have a compositionTime
return FLV_TAG_HEADER_SIZE + (flvtag_codecid_avc != flvtag_codecid (tag) ? 1 : (flvtag_frametype_commandframe != flvtag_frametype (tag) ? 5 : 2));
default:
return FLV_TAG_HEADER_SIZE;
}
}
size_t flvtag_payload_size (flvtag_t* tag)
{
return FLV_TAG_HEADER_SIZE + flvtag_size (tag) - flvtag_header_size (tag);
}
uint8_t* flvtag_payload_data (flvtag_t* tag)
{
size_t payload_offset = flvtag_header_size (tag);
return &tag->data[payload_offset];
}
////////////////////////////////////////////////////////////////////////////////
int flvtag_updatesize (flvtag_t* tag, uint32_t size)
{
tag->data[1] = size>>16; // DataSize
tag->data[2] = size>>8; // DataSize
tag->data[3] = size>>0; // DataSize
size += 11;
tag->data[size+0] = size>>24; // PrevTagSize
tag->data[size+1] = size>>16; // PrevTagSize
tag->data[size+2] = size>>8; // PrevTagSize
tag->data[size+3] = size>>0; // PrevTagSize
return 1;
}
#define FLVTAG_PREALOC 2048
int flvtag_initavc (flvtag_t* tag, uint32_t dts, int32_t cts, flvtag_frametype_t type)
{
flvtag_init (tag);
flvtag_reserve (tag,5+FLVTAG_PREALOC);
tag->data[0] = flvtag_type_video;
tag->data[4] = dts>>16;
tag->data[5] = dts>>8;
tag->data[6] = dts>>0;
tag->data[7] = dts>>24;
tag->data[8] = 0; // StreamID
tag->data[9] = 0; // StreamID
tag->data[10] = 0; // StreamID
// VideoTagHeader
tag->data[11] = ( (type<<4) %0xF0) |0x07; // CodecId
tag->data[12] = 0x01; // AVC NALU
tag->data[13] = cts>>16;
tag->data[14] = cts>>8;
tag->data[15] = cts>>0;
flvtag_updatesize (tag,5);
return 1;
}
int flvtag_initamf (flvtag_t* tag, uint32_t dts)
{
flvtag_init (tag);
flvtag_reserve (tag,FLVTAG_PREALOC);
tag->data[0] = flvtag_type_scriptdata;
tag->data[4] = dts>>16;
tag->data[5] = dts>>8;
tag->data[6] = dts>>0;
tag->data[7] = dts>>24;
tag->data[8] = 0; // StreamID
tag->data[9] = 0; // StreamID
tag->data[10] = 0; // StreamID
flvtag_updatesize (tag,0);
return 1;
}
// shamelessly taken from libtomcrypt, an public domain project
static void base64_encode (const unsigned char* in, unsigned long inlen, unsigned char* out, unsigned long* outlen)
{
static const char* codes = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
unsigned long i, len2, leven;
unsigned char* p;
/* valid output size ? */
len2 = 4 * ( (inlen + 2) / 3);
if (*outlen < len2 + 1) {
*outlen = len2 + 1;
fprintf (stderr,"\n\nHERE\n\n");
return;
}
p = out;
leven = 3* (inlen / 3);
for (i = 0; i < leven; i += 3) {
*p++ = codes[ (in[0] >> 2) & 0x3F];
*p++ = codes[ ( ( (in[0] & 3) << 4) + (in[1] >> 4)) & 0x3F];
*p++ = codes[ ( ( (in[1] & 0xf) << 2) + (in[2] >> 6)) & 0x3F];
*p++ = codes[in[2] & 0x3F];
in += 3;
}
if (i < inlen) {
unsigned a = in[0];
unsigned b = (i+1 < inlen) ? in[1] : 0;
*p++ = codes[ (a >> 2) & 0x3F];
*p++ = codes[ ( ( (a & 3) << 4) + (b >> 4)) & 0x3F];
*p++ = (i+1 < inlen) ? codes[ ( ( (b & 0xf) << 2)) & 0x3F] : '=';
*p++ = '=';
}
/* return ok */
*outlen = p - out;
}
const char onCaptionInfo708[] = { 0x02,0x00,0x0D, 'o','n','C','a','p','t','i','o','n','I','n','f','o',
0x08, 0x00, 0x00, 0x00, 0x02,
0x00, 0x04, 't','y','p','e',
0x02, 0x00, 0x03, '7','0','8',
0x00, 0x04, 'd','a','t','a',
0x02, 0x00,0x00
};
int flvtag_amfcaption_708 (flvtag_t* tag, uint32_t timestamp, sei_message_t* msg)
{
flvtag_initamf (tag,timestamp);
unsigned long size = 1 + (4 * ( (sei_message_size (msg) + 2) / 3));
flvtag_reserve (tag, sizeof (onCaptionInfo708) + size + 3);
memcpy (flvtag_payload_data (tag),onCaptionInfo708,sizeof (onCaptionInfo708));
uint8_t* data = flvtag_payload_data (tag) + sizeof (onCaptionInfo708);
base64_encode (sei_message_data (msg), sei_message_size (msg), data, &size);
// Update the size of the base64 string
data[-2] = size >> 8;
data[-1] = size >> 0;
// write the last array element
data[size+0] = 0x00;
data[size+1] = 0x00;
data[size+2] = 0x09;
flvtag_updatesize (tag, sizeof (onCaptionInfo708) + size + 3);
return 1;
}
const char onCaptionInfoUTF8[] = { 0x02,0x00,0x0D, 'o','n','C','a','p','t','i','o','n','I','n','f','o',
0x08, 0x00, 0x00, 0x00, 0x02,
0x00, 0x04, 't','y','p','e',
0x02, 0x00, 0x04, 'U','T','F','8',
0x00, 0x04, 'd','a','t','a',
0x02, 0x00,0x00
};
#define MAX_AMF_STRING 65636
int flvtag_amfcaption_utf8 (flvtag_t* tag, uint32_t timestamp, const utf8_char_t* text)
{
flvtag_initamf (tag,timestamp);
unsigned long size = strlen (text);
if (MAX_AMF_STRING < size) {
size = MAX_AMF_STRING;
}
flvtag_reserve (tag, sizeof (onCaptionInfoUTF8) + size + 3);
memcpy (flvtag_payload_data (tag),onCaptionInfoUTF8,sizeof (onCaptionInfoUTF8));
uint8_t* data = flvtag_payload_data (tag) + sizeof (onCaptionInfo708);
memcpy (data,text,size);
// Update the size of the string
data[-2] = size >> 8;
data[-1] = size >> 0;
// write the last array element
data[size+0] = 0x00;
data[size+1] = 0x00;
data[size+2] = 0x09;
flvtag_updatesize (tag, sizeof (onCaptionInfoUTF8) + size + 3);
return 1;
}
#define LENGTH_SIZE 4
int flvtag_avcwritenal (flvtag_t* tag, uint8_t* data, size_t size)
{
uint32_t flvsize = flvtag_size (tag);
flvtag_reserve (tag,flvsize+LENGTH_SIZE+size);
uint8_t* payload = tag->data + FLV_TAG_HEADER_SIZE + flvsize;
payload[0] = size>>24; // nalu size
payload[1] = size>>16;
payload[2] = size>>8;
payload[3] = size>>0;
memcpy (&payload[LENGTH_SIZE],data,size);
flvtag_updatesize (tag,flvsize+LENGTH_SIZE+size);
return 1;
}
int flvtag_addcaption (flvtag_t* tag, const utf8_char_t* text)
{
if (flvtag_avcpackettype_nalu != flvtag_avcpackettype (tag)) {
return 0;
}
sei_t sei;
caption_frame_t frame;
sei_init (&sei);
caption_frame_init (&frame);
caption_frame_from_text (&frame, text);
sei_from_caption_frame (&sei, &frame);
uint8_t* sei_data = malloc (sei_render_size (&sei));
size_t sei_size = sei_render (&sei, sei_data);
// rewrite tag
flvtag_t new_tag;
flvtag_initavc (&new_tag, flvtag_dts (tag), flvtag_cts (tag), flvtag_frametype (tag));
uint8_t* data = flvtag_payload_data (tag);
ssize_t size = flvtag_payload_size (tag);
while (0<size) {
uint8_t* nalu_data = &data[LENGTH_SIZE];
uint8_t nalu_type = nalu_data[0]&0x1F;
uint32_t nalu_size = (data[0]<<24) | (data[1]<<16) | (data[2]<<8) | data[3];
data += LENGTH_SIZE + nalu_size;
size -= LENGTH_SIZE + nalu_size;
if (0 < sei_size && 7 != nalu_type && 8 != nalu_type && 9 != nalu_type ) {
// fprintf (stderr,"Wrote SEI %d '%d'\n\n", sei_size, sei_data[3]);
flvtag_avcwritenal (&new_tag,sei_data,sei_size);
sei_size = 0;
}
flvtag_avcwritenal (&new_tag,nalu_data,nalu_size);
}
// On the off chance we have an empty frame,
// We still wish to append the sei
if (0<sei_size) {
// fprintf (stderr,"Wrote SEI %d\n\n", sei_size);
flvtag_avcwritenal (&new_tag,sei_data,sei_size);
sei_size = 0;
}
if (sei_data) {
free (sei_data);
}
free (tag->data);
sei_free (&sei);
tag->data = new_tag.data;
tag->aloc = new_tag.aloc;
return 1;
}