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The pirate bay depuis la Belgique
1er avril 2013, par
Mis à jour : Avril 2013
Langue : français
Type : Image
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Publier sur MédiaSpip
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Sur d’autres sites (6319)
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FFmpeg : undefined references to av_frame_alloc()
6 août 2014, par dontrythisathomeI want to get into FFmpeg developing and i started following these samples tutorial here : here
I started with the first tutorial - tutorial01.c - but i run into this problem ’undefined references to av_frame_alloc()’.
I’m on Ubuntu 12.04 LTS.
This is my program :
/*
* File: main.c
* Author: dontrythisathome
*
* Created on 3 giugno 2014, 23.02
*/
#include
#include <libavcodec></libavcodec>avcodec.h>
#include <libavformat></libavformat>avformat.h>
#include <libavutil></libavutil>frame.h>
#include <libswscale></libswscale>swscale.h>
/*
*
*/
void SaveFrame(AVFrame *pFrame, int width, int height, int iFrame)
{
FILE *pFile;
char szFilename[32];
int y;
//Apre il file
sprintf(szFilename, "frame%d.ppm", iFrame);
pFile=fopen(szFilename, "wb");
if(pFile==NULL)
{return; }
//Scrive l'intestazione del file ( Larghezza x Altezza su video)
fprintf(pFile, "P6\n%d %d\n255\n", width, height);
//Scrive i data pixel
for(y=0; ydata[0]+y*pFrame->linesize[0], 1, width*3, pFile);
}
//Chiude il file
fclose(pFile);
}
/*
*
*/
/*Main Function*/
int main(int argc, char *argv[])
{
AVFormatContext *pFormatCtx;
int i, videoStreamIdx;
AVCodecContext *pCodecCtx;
AVCodec *pCodec;
AVFrame *pFrame;
AVFrame *pFrameRGB;
AVPacket packet;
int frameFinished;
int numBytes;
uint8_t *buffer;
static struct SwsContext *img_convert_ctx;
if(argc < 2){
printf("Inserisci un file video\n");
return -1;
}
//Registra tutti i formati e i codec
av_register_all();
//Apre il file video
if(avformat_open_input(&pFormatCtx, argv[1], NULL, NULL) != 0)
{return -1;} //Impossibile aprire il file
//Recupera le informazioni dello stream
if(avformat_find_stream_info(pFormatCtx, NULL) < 0)
{return -1;} // Couldn't find stream information
//Versa le informazioni del file sullo standard error
av_dump_format(pFormatCtx, 0, argv[1], 0);
//Trova il primo stream video
videoStreamIdx=-1;
for(i=0; inb_streams; i++)
{
if(pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO)
{ videoStreamIdx=i;
break;}
}
if(videoStreamIdx==-1)
return -1; // Impossibile trovare lo stream video
// Punta al contenuto del codec per lo stream video
pCodecCtx = pFormatCtx->streams[videoStreamIdx]->codec;
// Trova il decoder per lo stream video
pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
if(pCodec==NULL)
{
fprintf(stderr, "Codec Non Supportato!\n");
return -1; //Impossibile trovare il codec
}
//Apre il codec
if(avcodec_open2(pCodecCtx, pCodec, NULL) < 0)
{return -1;} //Impossibile aprire il codec
//Alloca il frame video
pFrame = av_frame_alloc();
//Alloca una struct AVFrame
pFrameRGB = av_frame_alloc();
if(pFrameRGB==NULL)
{return -1;}
//Determina la grandezza necessaria per il buffer e lo alloca
numBytes = avpicture_get_size(PIX_FMT_RGB24,
pCodecCtx->width,
pCodecCtx->height);
buffer = (uint8_t *) av_malloc(numBytes*sizeof(uint8_t));
//Assegna le parti appropriate del buffer sulla superficie dell'immagine in pFrameRGB
//Tenere presente che pFrameRGB è un AVFrame, ma AVFrame è una superset di AVPicture
avpicture_fill((AVPicture *)pFrameRGB, buffer, PIX_FMT_RGB24, pCodecCtx->width, pCodecCtx->height);
int w = pCodecCtx->width;
int h = pCodecCtx->height;
img_convert_ctx = sws_getContext(w, h, pCodecCtx->pix_fmt,
w, h, PIX_FMT_RGB24,
SWS_LANCZOS, NULL, NULL, NULL);
//Legge i frame e salva i primi 5 frame su disco
i=0;
while((av_read_frame(pFormatCtx, &packet)>=0) && (i<5))
{
//Questo è il packet dello stream video?
if(packet.stream_index==videoStreamIdx)
{
//Decodifica il frame video
avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
//Si è riusiciti ad ottenere il frame video?
if(frameFinished)
{
i++;
sws_scale(img_convert_ctx, (const uint8_t * const *)pFrame->data,
pFrame->linesize, 0, pCodecCtx->height,
pFrameRGB->data, pFrameRGB->linesize);
SaveFrame(pFrameRGB, pCodecCtx->width, pCodecCtx->height, i);
}
}
//Libera il pacchetto che era allocato da av_read_frame
av_free_packet(&packet);
}
//Libera l'immagine RGB
av_free(buffer);
av_free(pFrameRGB);
//Libera il frame YUV
av_free(pFrame);
//Chiude il codec
avcodec_close(pCodecCtx);
//Chiude il file video
avformat_close_input(&pFormatCtx);
/*FINE PROGRAMMA*/
return 0;
}This is the build output :
"/usr/bin/make" -f nbproject/Makefile-Debug.mk QMAKE= SUBPROJECTS= .build-conf
make[1]: ingresso nella directory "/home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid"
"/usr/bin/make" -f nbproject/Makefile-Debug.mk dist/Debug/GNU-Linux-x86/simplemediaplayerforandroid
make[2]: ingresso nella directory "/home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid"
mkdir -p dist/Debug/GNU-Linux-x86
gcc -o dist/Debug/GNU-Linux-x86/simplemediaplayerforandroid build/Debug/GNU-Linux-x86/main.o -L/usr/lib/x86_64-linux-gnu -lavformat -lavcodec -lavutil -lswscale -lz -lbz2
build/Debug/GNU-Linux-x86/main.o: In function `main':
/home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid/main.c:105: undefined reference to `av_frame_alloc'
/home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid/main.c:108: undefined reference to `av_frame_alloc'
collect2: ld returned 1 exit status
make[2]: *** [dist/Debug/GNU-Linux-x86/simplemediaplayerforandroid] Errore 1
make[2]: uscita dalla directory "/home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid"
make[1]: *** [.build-conf] Errore 2
make[1]: uscita dalla directory "/home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid"
make: *** [.build-impl] Errore 2
BUILD FAILED (exit value 2, total time: 143ms)I also linked the correct library path and headers path because there is no error with that.
But when i try to build the program from the terminal with these commands :
gcc -o prog1 /home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid/main.c -lavformat -lavcodec -lavutil -lswscale -lz -lbz2And the output is different :
/home/dontrythisathome/Programmazione/C-C++/SimpleMediaPlayerForAndroid/main.c:11:29: fatal error: libavutil/frame.h: File o directory non esistente
compilation terminated.The output says that there is no file or directory existing.
What is the problem ? -
Reduce HLS latency from +30 seconds
4 juin 2014, par RickUbuntu 12.04
nginx 1.2.4
avconv -version
avconv version 0.8.10-4:0.8.10-0ubuntu0.12.04.1, Copyright (c) 2000-2013 the Libav developers
built on Feb 6 2014 20:56:59 with gcc 4.6.3
avconv 0.8.10-4:0.8.10-0ubuntu0.12.04.1
libavutil 51. 22. 2 / 51. 22. 2
libavcodec 53. 35. 0 / 53. 35. 0
libavformat 53. 21. 1 / 53. 21. 1
libavdevice 53. 2. 0 / 53. 2. 0
libavfilter 2. 15. 0 / 2. 15. 0
libswscale 2. 1. 0 / 2. 1. 0
libpostproc 52. 0. 0 / 52. 0. 0I’m using avconv and nginx to create an HLS stream but right now my latency is regularly well over 30 seconds. After much reading I am aware that HLS has built in latency and that 10s is expected and even preferred but 30s seems quite extreme.
I’ve seen a lot of discussion on the nginx-rtmp google group, this thread in particular had a lot of suggestions. I have attempted to reduce solve my issue by reducing the
hls_fragmentand thehls_playlist_lengthbut they haven’t had a significant effect.nginx.conf :
#user nobody;
worker_processes 1;
error_log logs/error.log debug;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
sendfile on;
keepalive_timeout 65;
server {
listen 8888;
server_name localhost;
add_header 'Access-Control-Allow-Origin' "*";
location /hls {
types {
application/vnd.apple.mpegurl m3u8;
video/mp2t ts;
}
root /tmp;
}
# rtmp stat
location /stat {
rtmp_stat all;
rtmp_stat_stylesheet stat.xsl;
}
location /stat.xsl {
# you can move stat.xsl to a different location
root /usr/build/nginx-rtmp-module;
}
# rtmp control
location /control {
rtmp_control all;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
}
}
rtmp {
server {
listen 1935;
ping 30s;
notify_method get;
application myapp {
live on;
hls on;
hls_path /tmp/hls;
hls_base_url http://x.x.x.x:8888/hls/;
hls_sync 2ms;
hls_fragment 2s;
#hls_variant _low BANDWIDTH=160000;
#hls_variant _mid BANDWIDTH=320000;
#hls_variant _hi BANDWIDTH=640000;
}
}
}avconv command :
avconv -r 30 -y -f image2pipe -codec:v mjpeg -i - -f flv -codec:v libx264 -profile:v baseline -preset ultrafast -tune zerolatency -an -f flv rtmp://127.0.0.1:1935/myapp/mystream -
Setting start date in gource
5 juin 2014, par rfc1484I’m trying to run gource from a certain date, but it reports me a ’codec not found error’.
This is the command without a start date :
gource -1280x720 --seconds-per-day 1 --stop-at-end --hide filenames --hide files --git-branch master --camera-mode track --output-ppm-stream - | ffmpeg -y -b 3000k -r 25 -f image2pipe -vcodec ppm -i - test.mp4Which works fine and generates the .mp4 file as expected.
This is the command with a start date :
gource -1280x720 --start-date '2014-01-01' --seconds-per-day 1 --stop-at-end --hide filenames --hide files --git-branch master --camera-mode track --output-ppm-stream - | ffmpeg -y -b 3000k -r 25 -f image2pipe -vcodec ppm -i - test.mp4Which doesn’t work and generates the following error message :
[image2pipe @ 0x78a600] Could not find codec parameters (Video : ppm)
Any suggestions on how to fix this ?
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