Recherche avancée
Médias (1)
-
Somos millones 1
21 juillet 2014, par
Mis à jour : Juin 2015
Langue : français
Type : Video
Autres articles (16)
-
Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
Déploiements possibles
31 janvier 2010, parDeux types de déploiements sont envisageable dépendant de deux aspects : La méthode d’installation envisagée (en standalone ou en ferme) ; Le nombre d’encodages journaliers et la fréquentation envisagés ;
L’encodage de vidéos est un processus lourd consommant énormément de ressources système (CPU et RAM), il est nécessaire de prendre tout cela en considération. Ce système n’est donc possible que sur un ou plusieurs serveurs dédiés.
Version mono serveur
La version mono serveur consiste à n’utiliser qu’une (...) -
XMP PHP
13 mai 2011, parDixit Wikipedia, XMP signifie :
Extensible Metadata Platform ou XMP est un format de métadonnées basé sur XML utilisé dans les applications PDF, de photographie et de graphisme. Il a été lancé par Adobe Systems en avril 2001 en étant intégré à la version 5.0 d’Adobe Acrobat.
Étant basé sur XML, il gère un ensemble de tags dynamiques pour l’utilisation dans le cadre du Web sémantique.
XMP permet d’enregistrer sous forme d’un document XML des informations relatives à un fichier : titre, auteur, historique (...)
Sur d’autres sites (6014)
-
libavcodec : Set hidden visibility on global symbols accessed from AArch64 assembly
11 juillet 2022, par Martin Storsjölibavcodec : Set hidden visibility on global symbols accessed from AArch64 assembly
The AArch64 assembly accesses those symbols directly, without
indirection via e.g. the GOT on ELF. In order for this not to
require text relocations, those symbols need to be resolved fully
at link time, i.e. those symbols can't be interposable.Normally, so far, this is achieved when linking shared libraries
in two ways ; we have a version script (libavcodec/libavcodec.v) which
marks all symbols that don't start with av* as local. Additionally,
we try to add -Wl,-Bsymbolic to the linker options if supported,
making sure that such symbol references are resolved fully at link
time, instead of making them interposable.When the libavcodec static library is linked into another shared
library, there's no guarantee that it uses similar options (even though
that would be favourable), which would end up requiring text relocations
in the AArch64 assembly.Explicitly mark the symbols that are accessed from AArch64 assembly
as hidden, so that they are resolved fully at link time even without
the version script and -Wl,-Bsymbolic.Signed-off-by : Martin Storsjö <martin@martin.st>
-
Getting and decoding video by RTP H264
29 novembre 2023, par AlekseiKraevParsing RTP H264.
WINAPI C. A queue from C++ has been applied, I repent.


RTP is generated using FFMPEG with the following command :
ffmpeg.exe -f gdigrab -framerate 25 -i desktop -s 853x480 -b:v 120000 -c:v libx264 -f rtp rtp ://127.0.0.1:8080


Parsing the incoming RTP/h264 stream and converting it to an RGB matrix.


video_H264_decode.h


#pragma once
#ifndef _VIDEO_H264_DECODE_SEND_H // Блокируем повторное включение этого модуля
#define _VIDEO_H264_DECODE_SEND_H
//******************************************************************************
// Section include
//******************************************************************************
#include "main.h"
#include 
//******************************************************************************
// Constants
//******************************************************************************

//******************************************************************************
// Type
//******************************************************************************
typedef struct {
 unsigned char* data;
 int size;
}RTPData_DType;

typedef struct 
{
 union
 {
 struct
 {
 char V:2; //Версия
 char P:1; //заполнение
 char X:1; //расширение
 char CC:4; //количество CSRC

 char M:1; //маркер (флаг последнего пакета AU),
 char PT:7; //полезная нагрузка (тип данных носителя полезной нагрузки RTP, H264 = 96)

 short sequence_number; //Порядковый номер: порядковый номер пакета RTP, увеличенный на 1.
 int time_stamp; //временная метка выборки медиа. 
 int SSRC; //Пакет данных имеет одинаковое происхождение.
 };
 unsigned char data[12];
 };
}RTPHeader_DType;
//******************************************************************************
// Global var
//******************************************************************************

//******************************************************************************
// Local function prototype
//******************************************************************************
UCHAR rtp_H264_recive_init(void);
UCHAR RTPStop(void);
//******************************************************************************
// Macros
//******************************************************************************
#define BYTE2_SWAP(X) ((((short)(X) & 0xff00) >> 8) |(((short)(X) & 0x00ff) << 8))
#endif
//******************************************************************************
// ENF OF FILE
//******************************************************************************


video_H264_decode.c


//******************************************************************************
//include
//******************************************************************************
#include "main.h"
/*#include "video_H264_decode.h"
#include 
#include 
#include <chrono>
#include 

#pragma comment(lib, "ws2_32.lib")
#include */
#include <iostream>
#include <queue>

extern "C" {
#include "libavformat/avformat.h"
#include "libavfilter/avfilter.h"
#include "libavdevice/avdevice.h"
#include "libswscale/swscale.h"
#include "libswresample/swresample.h"
#include "libpostproc/postprocess.h"
#include "libavcodec/avcodec.h"
}

#pragma comment(lib,"avcodec.lib")
#pragma comment(lib,"avdevice.lib")
#pragma comment(lib,"avfilter.lib")
#pragma comment(lib,"avformat.lib")
#pragma comment(lib,"avutil.lib")
#pragma comment(lib,"postproc.lib")
#pragma comment(lib,"swresample.lib")
#pragma comment(lib,"swscale.lib")

#pragma warning(disable: 4996)
//******************************************************************************
// Section for determining the variables used in the module
//******************************************************************************
//------------------------------------------------------------------------------
// Global
//------------------------------------------------------------------------------

//------------------------------------------------------------------------------
// Local
//------------------------------------------------------------------------------
const int inteval = 0x01000000;
BOOL FlagRTPActive = TRUE;

HANDLE hMutexRTPRecive;
HANDLE hSemaphoreRTP;
HANDLE hTreadRTPRecive;
HANDLE hTreadRTPDecode;


SOCKET RTPSocket; //socket UDP RTP
RTPData_DType packet;
RTPData_DType FU_buffer = { 0 };

std::queue q;
std::set<int> seq;

AVFormatContext* pAVFormatContext;
AVCodecContext* pAVCodecContext;
const AVCodec* pAVCodec;
AVFrame* pAVFrame;
AVFrame* AVFrameRGG;
SwsContext* pSwsContext;
AVPacket *pAVPacket;
AVCodecParserContext* pAVCodecParserContext;

UINT port;
//******************************************************************************
// Section of prototypes of local functions
//******************************************************************************
DWORD WINAPI rtp_H264_recive_Procedure(CONST LPVOID lpParam);
DWORD WINAPI rtp_decode_Procedure(CONST LPVOID lpParam);
char RTPSocketInit(void);
void RTPPacketParser(void);
char RTPSocketRecive(void);
void Decode_NaluToAVFrameRGG();
//******************************************************************************
// Section of the description of functions
//******************************************************************************
UCHAR rtp_H264_recive_init(void)
{
 hSemaphoreRTP = CreateSemaphore(
 NULL, // default security attributes
 0, // initial count
 1, // maximum count
 NULL); // unnamed semaphore

 hMutexRTPRecive = CreateMutex(
 NULL, // default security attributes
 FALSE, // initially not owned
 NULL); // unnamed mutex

 hTreadRTPRecive = CreateThread(NULL, NULL, rtp_H264_recive_Procedure, NULL, NULL, NULL);
 hTreadRTPDecode = CreateThread(NULL, NULL, rtp_decode_Procedure, NULL, NULL, NULL);

 return 0;
}
//------------------------------------------------------------------------------
UCHAR RTPStop(void)
{
 FlagRTPActive = FALSE;

 if (hSemaphoreRTP) CloseHandle(hSemaphoreRTP);
 if (hMutexRTPRecive) CloseHandle(hMutexRTPRecive);
 if (hTreadRTPRecive) CloseHandle(hTreadRTPRecive);

 closesocket(RTPSocket); 

 return 0;
}
//------------------------------------------------------------------------------
DWORD WINAPI rtp_H264_recive_Procedure(CONST LPVOID lpParam)
{
 while (RTPSocketInit() == 0)
 Sleep(2000);
 
 while (1)
 {
 RTPSocketRecive();
 RTPPacketParser();
 ReleaseSemaphore(hSemaphoreRTP, 1, NULL);
 }
}
//------------------------------------------------------------------------------
DWORD WINAPI rtp_decode_Procedure(CONST LPVOID lpParam)
{
 port = param.Option.VideoPort;

 pAVPacket = av_packet_alloc();
 if (!pAVPacket)
 {
 MessageBox(NULL, L"ERROR Could not allocate pAVPacket", L"Init decoder error", MB_OK | MB_ICONERROR);
 exit(1);
 }
 av_init_packet(pAVPacket);

 /* find the MPEG-1 video decoder */
 pAVCodec = avcodec_find_decoder(AV_CODEC_ID_H264);
 if (!pAVCodec)
 {
 MessageBox(NULL, L"ERROR Codec not found", L"Init decoder error", MB_OK | MB_ICONERROR);
 exit(1);
 }

 pAVCodecParserContext = av_parser_init(pAVCodec->id);
 if (!pAVCodecParserContext)
 {
 MessageBox(NULL, L"ERROR Parser not found", L"Init decoder error", MB_OK | MB_ICONERROR);
 exit(1);
 }

 pAVCodecContext = avcodec_alloc_context3(pAVCodec);
 if (!pAVCodecContext) 
 {
 MessageBox(NULL, L"ERROR Could not allocate video codec context", L"Init decoder error", MB_OK | MB_ICONERROR);
 exit(1);
 }
 
 if (avcodec_open2(pAVCodecContext, pAVCodec, NULL) < 0)
 {
 MessageBox(NULL, L"ERROR Could not open codec", L"Init decoder error", MB_OK | MB_ICONERROR);
 exit(1);
 }

 pAVFrame = av_frame_alloc();
 if (!pAVFrame) 
 {
 MessageBox(NULL, L"ERROR Could not allocate video frame", L"Init decoder error", MB_OK | MB_ICONERROR);
 exit(1);
 } 
 
 while (FlagRTPActive)
 {
 if(port != param.Option.VideoPort)
 closesocket(RTPSocket);

 WaitForSingleObject(hSemaphoreRTP, 500); 
 Decode_NaluToAVFrameRGG();
 }

 avformat_free_context(pAVFormatContext);
 av_frame_free(&pAVFrame);
 avcodec_close(pAVCodecContext);
 av_packet_free(&pAVPacket);

 
 if (hTreadRTPDecode) CloseHandle(hTreadRTPDecode);

 return 0;
}

//------------------------------------------------------------------------------
char RTPSocketInit(void)
{ 
 sockaddr_in RTPSocketAddr;
 
 RTPSocketAddr.sin_family = AF_INET;
 RTPSocketAddr.sin_addr.s_addr = htonl(INADDR_ANY);
 RTPSocketAddr.sin_port = htons(param.Option.VideoPort);

 RTPSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 if (RTPSocket == INVALID_SOCKET)
 {
 MessageBox(NULL, L"ERROR Invalid RTP Socket", L"UDP Socket", MB_OK | MB_ICONERROR);
 return 0;
 }

 int option = 12000;
 if (setsockopt(RTPSocket, SOL_SOCKET, SO_RCVBUF, (char*)&option, sizeof(option)) < 0)
 {
 printf("setsockopt failed\n");

 }

 /*option = TRUE;
 if (setsockopt(RTPSocket, SOL_SOCKET, SO_CONDITIONAL_ACCEPT, (char*)&option, sizeof(option)) < 0)
 {
 printf("setsockopt failed\n");

 }*/

 if (bind(RTPSocket, (sockaddr*)&RTPSocketAddr, sizeof(RTPSocketAddr)) == SOCKET_ERROR)
 {
 MessageBox(NULL, L"ERROR bind", L"UDP Socket", MB_OK | MB_ICONERROR);
 closesocket(RTPSocket);
 return 0;
 }
 return 1;
}

//------------------------------------------------------------------------------
char RTPSocketRecive(void)
{
 static char RecvBuf[2000];
 static int BufLen = 2000;

 int iResult = 0;
 struct sockaddr_in SenderAddr;
 int SenderAddrSize = sizeof(SenderAddr);
 TCHAR szErrorMsg[100];

 iResult = recvfrom(RTPSocket, RecvBuf, BufLen, 0, NULL, NULL);
 if (iResult == SOCKET_ERROR && FlagRTPActive == TRUE)
 {
 StringCchPrintf(szErrorMsg, 100, L"ERROR recvfrom Ошибка:%d", WSAGetLastError());
 MessageBox(NULL, szErrorMsg, L"UDP Socket", MB_OK | MB_ICONERROR);
 return -1;
 }

 packet.data = (unsigned char*)RecvBuf;
 packet.size = iResult;

 return 1;
}

//------------------------------------------------------------------------------
void RTPPacketParser(void)
{
 RTPHeader_DType RTPHeader;
 RTPData_DType NALU;
 unsigned char* buffer = packet.data;
 int pos = 0;
 static int count = 0;
 static short lastSequenceNumber = 0xFFFF;
 short type;
 char payload_header;

 //read rtp header
 memcpy(&RTPHeader, buffer, sizeof(RTPHeader));
 RTPHeader.sequence_number = BYTE2_SWAP(RTPHeader.sequence_number);
 pos += 12; 
 
 if (RTPHeader.X) {
 //profile extension
 short define;
 short length;
 length = buffer[pos + 3];//suppose not so long extension
 pos += 4;
 pos += (length * 4);
 }

 payload_header = buffer[pos];
 type = payload_header & 0x1f; //Тип полезной нагрузки RTP
 pos++;
 
 //STAP-A
 if (type == 24)
 { 
 while (pos < packet.size)
 {
 unsigned short NALU_size;
 memcpy(&NALU_size, buffer + pos, 2);
 NALU_size = BYTE2_SWAP(NALU_size);
 pos += 2;
 char NAL_header = buffer[pos];
 short NAL_type = NAL_header & 0x1f;

 if (NAL_type == 7) 
 {
 count++;
 //cout<<"SPS, sequence number: "</cout<<"PPS, sequence number: "</cout<<"end of sequence, sequence number: "< 0) 
 {
 NALU.data = (unsigned char*) malloc(NALU_size + 4);
 NALU.size = NALU_size + 4;
 memcpy(NALU.data, &inteval, 4);
 memcpy(NALU.data + 4, &buffer[pos], NALU_size);

 WaitForSingleObject(hMutexRTPRecive, INFINITE);
 q.push(NALU);
 ReleaseMutex(hMutexRTPRecive);
 }

 pos += NALU_size;
 }
 }
 //FU-A Fragmentation unit
 else if (type == 28)
 { 
 //FU header
 char FU_header = buffer[pos];
 bool fStart = FU_header & 0x80;
 bool fEnd = FU_header & 0x40;

 //NAL header
 char NAL_header = (payload_header & 0xe0) | (FU_header & 0x1f);
 short NAL_type = FU_header & 0x1f;
 if (NAL_type == 7) 
 {
 count++;
 //SPS
 }
 else if (NAL_type == 8) 
 {
 //PPS
 }
 else if (NAL_type == 10) 
 {
 //end of sequence
 }
 pos++;

 int size = packet.size - pos;
 
 if (count > 0)
 {
 if (fStart) 
 {
 if (FU_buffer.size != 0)
 {
 free(FU_buffer.data);
 FU_buffer.size = 0;
 }
 FU_buffer.data = (unsigned char*)malloc(size + 5);
 if (FU_buffer.data == NULL)
 return;
 FU_buffer.size = size + 5;
 memcpy(FU_buffer.data, &inteval, 4);
 memcpy(FU_buffer.data + 4, &NAL_header, 1);
 memcpy(FU_buffer.data + 5, buffer + pos, size);
 }
 else
 {
 unsigned char* temp = (unsigned char*)malloc(FU_buffer.size + size);
 memcpy(temp, FU_buffer.data, FU_buffer.size);
 memcpy(temp + FU_buffer.size, buffer + pos, size);
 if (FU_buffer.size != 0) free(FU_buffer.data);
 FU_buffer.data = temp;
 FU_buffer.size += size;
 }

 if (fEnd)
 {
 NALU.data = (unsigned char*)malloc(FU_buffer.size);
 NALU.size = FU_buffer.size;
 memcpy(NALU.data, FU_buffer.data, FU_buffer.size);

 WaitForSingleObject(hMutexRTPRecive, INFINITE);
 q.push(NALU);
 ReleaseMutex(hMutexRTPRecive);

 free(FU_buffer.data);
 FU_buffer.size = 0;
 }
 }
 
 }
 else 
 {
 //other type
 short NAL_type = type;
 if (NAL_type == 7) 
 {
 count++;
 //SPS
 }
 else if (NAL_type == 8) 
 {
 //PPS
 }
 else if (NAL_type == 10) 
 {
 //end of sequence
 }

 int size = packet.size - pos + 1;
 if (count > 0)
 {
 NALU.data = (unsigned char*)malloc(size+4);
 NALU.size = size + 4;
 memcpy(NALU.data, &inteval, 4);
 memcpy(NALU.data + 4, &buffer[12], size);

 WaitForSingleObject(hMutexRTPRecive, INFINITE);
 q.push(NALU);
 ReleaseMutex(hMutexRTPRecive);
 }
 }
}

//------------------------------------------------------------------------------
void Decode_NaluToAVFrameRGG()
{
 unsigned char cntNALU;
 int len = 0;
 static int size = 0;
 unsigned char* data = NULL;
 int ret;
 RTPData_DType NALU;

 av_frame_unref(pAVFrame);
 av_packet_unref(pAVPacket);

 while(1)
 {
 WaitForSingleObject(hMutexRTPRecive, INFINITE);
 if (q.empty())
 {
 ReleaseMutex(hMutexRTPRecive);
 break;
 }
 NALU = q.front();
 q.pop();
 ReleaseMutex(hMutexRTPRecive);

 data = NALU.data;
 size = NALU.size;

 while(size)
 { 
 len = av_parser_parse2(pAVCodecParserContext, pAVCodecContext, &pAVPacket->data, &pAVPacket->size,
 (uint8_t*)data, size,
 AV_NOPTS_VALUE, AV_NOPTS_VALUE, AV_NOPTS_VALUE);

 data = len ? data + len : data;
 size -= len;
 
 if (pAVPacket->size)
 {
 ret = avcodec_send_packet(pAVCodecContext, pAVPacket);

 if(ret == AVERROR_EOF)
 MessageBox(NULL, L"the codec has been fully flushed, and there will be no more output frames", L"avcodec_send_packet", MB_OK | MB_ICONERROR);

 if (ret < 0)
 {
 MessageBox(NULL, L"ERROR sending a packet for decoding", L"Decode", MB_OK | MB_ICONERROR);
 //exit(1);
 }

 while (ret >= 0) 
 {
 ret = avcodec_receive_frame(pAVCodecContext, pAVFrame);
 if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
 break;
 else if (ret < 0) {
 MessageBox(NULL, L"ERROR during decoding", L"Decode", MB_OK | MB_ICONERROR);
 //exit(1);
 }
 
 AVFrameRGG = av_frame_alloc(); 
 pSwsContext = sws_getContext(pAVCodecContext->width, pAVCodecContext->height, pAVCodecContext->pix_fmt,
 pAVCodecContext->width, pAVCodecContext->height, AV_PIX_FMT_RGB24, SWS_SPLINE,
 0, 0, 0);

 sws_scale_frame(pSwsContext, AVFrameRGG, pAVFrame);
 
 ImgBufferSet(AVFrameRGG->data[0], pAVCodecContext->height, pAVCodecContext->width, AVFrameRGG->linesize[0]);

 sws_freeContext(pSwsContext);
 av_frame_free(&AVFrameRGG);
 }
 }
 }
 free(NALU.data);
 NALU.size = 0;
 } 
}

</int></queue></iostream></chrono>

It's DECIDED


-
lavd/x11grab : fix vertical repositioning
28 mars 2019, par Octavio Alvarezlavd/x11grab : fix vertical repositioning
There is a calculation error in xcbgrab_reposition() that breaks
vertical repositioning on follow_mouse. It made the bottom
reposition occur when moving the mouse lower than N pixels after
the capture bottom edge, instead of before.This commit fixes the calculation to match the documentation.
follow_mouse : centered or number of pixels. The documentation says :
When it is specified with "centered", the grabbing region follows
the mouse pointer and keeps the pointer at the center of region ;
otherwise, the region follows only when the mouse pointer reaches
within PIXELS (greater than zero) to the edge of region.
Syndiquer tout le site
