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999,999
26 septembre 2011, par
Mis à jour : Septembre 2011
Langue : English
Type : Audio
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The Slip - Artworks
26 septembre 2011, par
Mis à jour : Septembre 2011
Langue : English
Type : Texte
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Demon seed (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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The four of us are dying (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Corona radiata (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Lights in the sky (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
Autres articles (90)
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Ajouter notes et légendes aux images
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Gestion générale des documents
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Les vidéos
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Sur d’autres sites (8087)
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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.mkv
I 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
-
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.mkv
I 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
-
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);
}