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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (69)
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Websites made with MediaSPIP
2 mai 2011, parThis page lists some websites based on MediaSPIP.
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Creating farms of unique websites
13 avril 2011, parMediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...) -
(Dés)Activation de fonctionnalités (plugins)
18 février 2011, parPour gérer l’ajout et la suppression de fonctionnalités supplémentaires (ou plugins), MediaSPIP utilise à partir de la version 0.2 SVP.
SVP permet l’activation facile de plugins depuis l’espace de configuration de MediaSPIP.
Pour y accéder, il suffit de se rendre dans l’espace de configuration puis de se rendre sur la page "Gestion des plugins".
MediaSPIP est fourni par défaut avec l’ensemble des plugins dits "compatibles", ils ont été testés et intégrés afin de fonctionner parfaitement avec chaque (...)
Sur d’autres sites (7461)
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Improve ffmpeg CPU usage by compramising quality
20 juin 2015, par Hardik JunejaI am using FFMpeg for screen capturing.
I am looking for a screen capturing tool that will run on 1000 of VMs (windows and mac).The VMs have limited CPU (1 core) and 2GB ram and No GPU.Currently I invoke ffmpeg with
ffmpeg -y -framerate 8 -f dshow -f gdigrab -i "desktop" -c:v libx264 -crf 0 -preset ultrafast -threads 0 temp.mkvI am using gdigrab to capture screen ? Is there any better options that might reduce cpu usage ? or changing the encoder or format ?
I am aiming for 4-5% reduction in CPU usage.
Thanks in advance
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Android bytedeco javacpp ffmpeg decode h264 bytes to yuv and render with openGL ES 2.0. Wrong colors
9 juin 2015, par tema_manthere ! I try to display a video stream, which comes from server as byte array.
Data in this array is h264 encoded image and i decode it with bytedeco javacpp-presets library in this way :public class DMDecoder {
private static final String LOG_TAG = "DMDecoder";
private AVCodec avCodec;
private AVCodecContext avCodecContext;
private AVFrame avFrame;
private AVPacket avPacket;
private boolean wasIFrame;
private long IFrameTimeStampMs;
private int maxFps;
private int codecId;
private DMDecoderCallback callback;
public DMDecoder(DMDecoderCallback cb) {
this.callback = cb;
this.codecId = AV_CODEC_ID_H264;
avcodec_register_all();
restart();
}
public void restart() {
stop();
start();
}
public void stop() {
frames = 0;
if (avCodecContext != null) {
avcodec_close(avCodecContext);
avcodec_free_context(avCodecContext);
avCodecContext = null;
}
if (avCodec != null) {
av_free(avCodec);
avCodec = null;
}
if (avFrame != null) {
av_frame_free(avFrame);
avFrame = null;
}
if (avPacket != null) {
av_free_packet(avPacket);
avPacket = null;
}
}
public void start() {
avCodec = avcodec_find_decoder(codecId);
avCodecContext = avcodec_alloc_context3(avCodec);
AVDictionary opts = new AVDictionary();
avcodec_open2(avCodecContext, avCodec, opts);
avFrame = av_frame_alloc();
avPacket = new AVPacket();
av_init_packet(avPacket);
}
public VideoFrame decode(byte[] data, int dataOffset, int dataSize) {
avPacket.pts(AV_NOPTS_VALUE);
avPacket.dts(AV_NOPTS_VALUE);
avPacket.data(new BytePointer(data).position(dataOffset));
avPacket.size(dataSize);
avPacket.pos(-1);
IntBuffer gotPicture = IntBuffer.allocate(1);
int processedBytes = avcodec_decode_video2(
avCodecContext, avFrame, gotPicture, avPacket);
if (avFrame.width() == 0 || avFrame.height() == 0) return null;
VideoFrame frame = new VideoFrame();
frame.colorPlane0 = new byte[avFrame.width() * avFrame.height()];
frame.colorPlane1 = new byte[avFrame.width() / 2 * avFrame.height() / 2];
frame.colorPlane2 = new byte[avFrame.width() / 2 * avFrame.height() / 2];
if (avFrame.data(0) != null) avFrame.data(0).get(frame.colorPlane0);
if (avFrame.data(1) != null) avFrame.data(1).get(frame.colorPlane1);
if (avFrame.data(2) != null) avFrame.data(2).get(frame.colorPlane2);
frame.lineSize0 = avFrame.width();
frame.lineSize1 = avFrame.width() / 2;
frame.lineSize2 = avFrame.width() / 2;
frame.width = avFrame.width();
frame.height = avFrame.height();
return frame;
}
}VideoFrame class is just simple POJO :
public class VideoFrame {
public byte[] colorPlane0;
public byte[] colorPlane1;
public byte[] colorPlane2;
public int lineSize0;
public int lineSize1;
public int lineSize2;
public int width;
public int height;
public long presentationTime;
}After decoding i send this frame to my GLRenderer class
public class GLRenderer implements GLSurfaceView.Renderer {
private static final String LOG_TAG = "GLRenderer";
private TexturePlane plane;
private ConcurrentLinkedQueue<videoframe> frames;
private int maxFps = 30;
private VideoFrame currentFrame;
private long startTime, endTime;
private int viewWidth, viewHeight;
private boolean isFirstFrameProcessed;
public GLRenderer(int viewWidth, int viewHeight) {
frames = new ConcurrentLinkedQueue<>();
this.viewWidth = viewWidth;
this.viewHeight = viewHeight;
}
// mMVPMatrix is an abbreviation for "Model View Projection Matrix"
private final float[] mMVPMatrix = new float[16];
private final float[] mProjectionMatrix = new float[16];
private final float[] mViewMatrix = new float[16];
@Override
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
// Set the background frame color
GLES20.glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
plane = new TexturePlane();
}
public void setMaxFps(int maxFps) {
this.maxFps = maxFps;
}
@Override
public void onDrawFrame(GL10 unused) {
// Draw background color
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
// Set the camera position (View matrix)
Matrix.setLookAtM(mViewMatrix, 0, 0, 0, -3, 0f, 0f, 0f, 0f, 1.0f, 0.0f);
// Calculate the projection and view transformation
Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mViewMatrix, 0);
if (!isFirstFrameProcessed) checkViewPort(viewWidth, viewHeight);
if (maxFps > 0 && startTime > 0) {
endTime = System.currentTimeMillis();
long time = endTime - startTime;
//
long wantedTime = 1000 / maxFps;
//
long wait;
if (time < wantedTime) {
wait = wantedTime - time;
//
try {
Thread.sleep(wait);
} catch (InterruptedException e) {
Log.e(LOG_TAG, "thread interrupted exception");
}
}
}
startTime = System.currentTimeMillis();
tick();
plane.draw(mMVPMatrix);
}
private void updateFrame(VideoFrame frame) {
plane.updateTexture(frame.colorPlane0, frame.width, frame.height, 0);
plane.updateTexture(frame.colorPlane1, frame.width / 2, frame.height / 2, 1);
plane.updateTexture(frame.colorPlane2, frame.width / 2, frame.height / 2, 2);
plane.setTextureWidth(frame.width);
plane.setTextureHeight(frame.height);
}
private void tick() {
if (frames.isEmpty()) return;
VideoFrame frame = frames.peek();
if (frame == null) return;
long tms = System.currentTimeMillis();
if (frame.presentationTime <= tms) {
updateFrame(frame);
currentFrame = frame;
frames.remove(frame);
}
}
@Override
public void onSurfaceChanged(GL10 unused, int width, int height) {
checkViewPort(width, height);
viewWidth = width;
viewHeight = height;
plane.setTextureWidth(width);
plane.setTextureHeight(height);
}
private void checkViewPort(int width, int height) {
float viewRatio = (float) width / height;
if (currentFrame != null) {
float targetRatio = (float) currentFrame.width / currentFrame.height;
int x, y, newWidth, newHeight;
if (targetRatio > viewRatio) {
newWidth = width;
newHeight = (int) (width / targetRatio);
x = 0;
y = (height - newHeight) / 2;
} else {
newHeight = height;
newWidth = (int) (height * targetRatio);
y = 0;
x = (width - newWidth) / 2;
}
GLES20.glViewport(x, y, newWidth, newHeight);
} else {
GLES20.glViewport(0, 0, width, height);
}
Matrix.frustumM(mProjectionMatrix, 0, 1, -1, -1, 1, 3, 4);
}
public void addFrame(VideoFrame frame) {
if (frame != null) {
frames.add(frame);
}
}
}
</videoframe>GLRenderer works with simple openGL polygon, on which i draw all textures
public class TexturePlane {
private static final String LOG_TAG = "TexturePlane";
private final String vertexShaderCode = "" +
"uniform mat4 uMVPMatrix;" +
"attribute vec4 vPosition;" +
"attribute vec2 a_TexCoordinate;" +
"varying vec2 v_TexCoordinate;" +
"void main() {" +
" gl_Position = uMVPMatrix * vPosition;" +
" v_TexCoordinate = a_TexCoordinate;" +
"}";
private final String fragmentShaderCode = "" +
"precision mediump float;" +
"varying vec2 v_TexCoordinate;" +
"uniform sampler2D s_texture_y;" +
"uniform sampler2D s_texture_u;" +
"uniform sampler2D s_texture_v;" +
"void main() {" +
" float y = texture2D(s_texture_y, v_TexCoordinate).r;" +
" float u = texture2D(s_texture_u, v_TexCoordinate).r - 0.5;" +
" float v = texture2D(s_texture_v, v_TexCoordinate).r - 0.5;" +
" float r = y + 1.13983 * v;" +
" float g = y - 0.39465 * u - 0.58060 * v;" +
" float b = y + 2.03211 * u;" +
" gl_FragColor = vec4(r, g, b, 1.0);" +
"}";
private final FloatBuffer vertexBuffer;
private final FloatBuffer textureBuffer;
private final ShortBuffer drawListBuffer;
private final int mProgram;
private int mPositionHandle;
private int mMVPMatrixHandle;
// number of coordinates per vertex in this array
private static final int COORDS_PER_VERTEX = 3;
private static final int COORDS_PER_TEXTURE = 2;
private static float squareCoords[] = {
-1f, 1f, 0.0f,
-1f, -1f, 0.0f,
1f, -1f, 0.0f,
1f, 1f, 0.0f
};
private static float uvs[] = {
0.0f, 0.0f,
0.0f, 1.0f,
1.0f, 1.0f,
1.0f, 0.0f
};
private final short drawOrder[] = {0, 1, 2, 0, 2, 3}; // order to draw vertices
private final int vertexStride = COORDS_PER_VERTEX * 4; // 4 bytes per vertex
private int textureWidth = 640;
private int textureHeight = 480;
private int yTextureUniformHandle;
private int uTextureUniformHandle;
private int vTextureUniformHandle;
private int yTextureHandle;
private int uTextureHandle;
private int vTextureHandle;
private int mTextureCoordinateHandle;
public void setTextureWidth(int textureWidth) {
this.textureWidth = textureWidth;
}
public int getTextureWidth() {
return textureWidth;
}
public void setTextureHeight(int textureHeight) {
this.textureHeight = textureHeight;
}
public int getTextureHeight() {
return textureHeight;
}
/**
* Sets up the drawing object data for use in an OpenGL ES context.
*/
public TexturePlane() {
// initialize vertex byte buffer for shape coordinates
ByteBuffer bb = ByteBuffer.allocateDirect(squareCoords.length * 4);
bb.order(ByteOrder.nativeOrder());
vertexBuffer = bb.asFloatBuffer();
vertexBuffer.put(squareCoords);
vertexBuffer.position(0);
// initialize byte buffer for the draw list
ByteBuffer dlb = ByteBuffer.allocateDirect(drawOrder.length * 2);
dlb.order(ByteOrder.nativeOrder());
drawListBuffer = dlb.asShortBuffer();
drawListBuffer.put(drawOrder);
drawListBuffer.position(0);
// initialize byte buffer for the draw list
ByteBuffer tbb = ByteBuffer.allocateDirect(uvs.length * 4);
tbb.order(ByteOrder.nativeOrder());
textureBuffer = tbb.asFloatBuffer();
textureBuffer.put(uvs);
textureBuffer.position(0);
mProgram = GLES20.glCreateProgram(); // create empty OpenGL Program
compileShaders();
setupTextures();
}
public void setupTextures() {
yTextureHandle = setupTexture(null, textureWidth, textureHeight, 0);
uTextureHandle = setupTexture(null, textureWidth, textureHeight, 1);
vTextureHandle = setupTexture(null, textureWidth, textureHeight, 2);
}
public int setupTexture(ByteBuffer data, int width, int height, int index) {
final int[] textureHandle = new int[1];
GLES20.glGenTextures(1, textureHandle, 0);
if (textureHandle[0] != 0) {
// Bind to the texture in OpenGL
GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + index);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureHandle[0]);
updateTexture(data, width, height, index);
// Set filtering
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_LINEAR);
// Set wrapping mode
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_REPEAT);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_REPEAT);
}
if (textureHandle[0] == 0) {
Log.e(LOG_TAG, "Error loading texture.");
}
return textureHandle[0];
}
public void updateTexture(byte[] data, int width, int height, int index) {
if (data == null) {
if (width == 0 || height == 0) {
width = textureWidth;
height = textureHeight;
}
data = new byte[width * height];
if (index == 0) {
Arrays.fill(data, y);
} else if (index == 1) {
Arrays.fill(data, u);
} else {
Arrays.fill(data, v);
}
}
byteBuffer.wrap(data);
byteBuffer.position(0);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + index);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE,
width, height, 0, GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, byteBuffer);
}
private void compileShaders() {
// prepare shaders and OpenGL program
int vertexShader = loadShader(
GLES20.GL_VERTEX_SHADER,
vertexShaderCode);
int fragmentShader = loadShader(
GLES20.GL_FRAGMENT_SHADER,
fragmentShaderCode);
GLES20.glAttachShader(mProgram, vertexShader); // add the vertex shader to program
GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program
GLES20.glLinkProgram(mProgram); // create OpenGL program executables
checkGlError("glLinkProgram");
// Add program to OpenGL environment
GLES20.glUseProgram(mProgram);
mPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition");
mTextureCoordinateHandle = GLES20.glGetAttribLocation(mProgram, "a_TexCoordinate");
GLES20.glEnableVertexAttribArray(mPositionHandle);
GLES20.glEnableVertexAttribArray(mTextureCoordinateHandle);
yTextureUniformHandle = GLES20.glGetUniformLocation(mProgram, "s_texture_y");
uTextureUniformHandle = GLES20.glGetUniformLocation(mProgram, "s_Texture_u");
vTextureUniformHandle = GLES20.glGetUniformLocation(mProgram, "s_Texture_v");
mMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
checkGlError("glGetUniformLocation");
}
/**
* Utility method for compiling a OpenGL shader.
* <p></p>
* <p><strong>Note:</strong> When developing shaders, use the checkGlError()
* method to debug shader coding errors.</p>
*
* @param type - Vertex or fragment shader type.
* @param shaderCode - String containing the shader code.
* @return - Returns an id for the shader.
*/
public int loadShader(int type, String shaderCode) {
// create a vertex shader type (GLES20.GL_VERTEX_SHADER)
// or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
int shader = GLES20.glCreateShader(type);
// add the source code to the shader and compile it
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
/**
* Utility method for debugging OpenGL calls. Provide the name of the call
* just after making it:
* <p></p>
* <pre>
* mColorHandle = GLES20.glGetUniformLocation(mProgram, "vColor");
* MyGLRenderer.checkGlError("glGetUniformLocation");</pre>
*
* If the operation is not successful, the check throws an error.
*
* @param glOperation - Name of the OpenGL call to check.
*/
public void checkGlError(String glOperation) {
int error;
String errorString;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
errorString = GLU.gluErrorString(error);
String message = glOperation + ": glError " + error + ": " + errorString;
Log.e(LOG_TAG, message);
throw new RuntimeException(message);
}
}
public void draw(float[] mvpMatrix) {
// Prepare the triangle coordinate data
GLES20.glVertexAttribPointer(
mPositionHandle, COORDS_PER_VERTEX,
GLES20.GL_FLOAT, false,
vertexStride, vertexBuffer);
GLES20.glVertexAttribPointer(
mTextureCoordinateHandle, COORDS_PER_TEXTURE,
GLES20.GL_FLOAT, false,
0, textureBuffer);
GLES20.glUniformMatrix4fv(mMVPMatrixHandle, 1, false, mvpMatrix, 0);
checkGlError("glUniformMatrix4fv");
GLES20.glUniform1i(yTextureUniformHandle, 0);
GLES20.glUniform1i(uTextureUniformHandle, 1);
GLES20.glUniform1i(vTextureUniformHandle, 2);
// Draw the square
GLES20.glDrawElements(
GLES20.GL_TRIANGLES, drawOrder.length,
GLES20.GL_UNSIGNED_SHORT, drawListBuffer);
}
}But i have a problem there. My GL surface display image with wrong colors. image
What i’m doing wrong ?
UPDATE :
As Ronald S. Bultje say, i added glBindTexture(...) function in my code. And now updateTexture(...) method looks like this :
public void updateTexture(byte[] data, int width, int height, int index) {
if (data == null) {
if (width == 0 || height == 0) {
width = textureWidth;
height = textureHeight;
}
data = new byte[width * height];
if (index == 0) {
Arrays.fill(data, y);
} else if (index == 1) {
Arrays.fill(data, u);
} else {
Arrays.fill(data, v);
}
}
byteBuffer.wrap(data);
byteBuffer.position(0);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0 + index);
int textureHandle = index == 0 ? yTextureHandle : index == 1 ? uTextureHandle : vTextureHandle;
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureHandle);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE,
width, height, 0, GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, byteBuffer);
} -
Streaming full HD using lighttpd streaming
2 juin 2015, par HD QualityWe have 1000 of HD full length movies and streaming using lighttpd all the files are converted using FFMPEG .FLV format, and we got VPS(Cent OS) 2TB storage & CPU : 6 cores & 30 GB RAM & 1 Gbit/s port.
when we get traffic player buffering very long time means 10min to start play,i spend searching google and tried all the possible way to improve but no luck.
can any one suggest how other sites are running without buffer issue,
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