Recherche avancée

Médias (2)

Mot : - Tags -/rotation

Autres articles (105)

  • Multilang : améliorer l’interface pour les blocs multilingues

    18 février 2011, par

    Multilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
    Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela.

  • Gestion des droits de création et d’édition des objets

    8 février 2011, par

    Par défaut, beaucoup de fonctionnalités sont limitées aux administrateurs mais restent configurables indépendamment pour modifier leur statut minimal d’utilisation notamment : la rédaction de contenus sur le site modifiables dans la gestion des templates de formulaires ; l’ajout de notes aux articles ; l’ajout de légendes et d’annotations sur les images ;

  • Le profil des utilisateurs

    12 avril 2011, par

    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
    L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...)

Sur d’autres sites (11216)

  • How to draw lines or shapes on an AVFrame ?

    14 juillet 2016, par eruslu

    I wanna draw video overlays like lines, circles, rectangles and print texts on an AVFrame by using the ffmpeg’s functions, not command line utility.

    Is there any one knows how to do it ?

    Do you have the source code for this function ?

  • YUV decoded by FFMPEG that draw with opengl is not clear

    3 juin 2016, par S.Jin

    I’m writing a movie player that use FFMPEG and OpenGL ES. Movie can be decoded succeessfully, but when I use AVFrame as texture to draw in my screen, I found it was so fuzzy. I don’t know where wrong in my code. If I change the AVFrame from YUV to RGB image, it will be clear.
    Does any one know why use YUV as texture to draw will be not clear ?

    My render code :

    #import "SJGLView.h"
    #import <glkit></glkit>GLKit.h>
    #import "SJDecoder.h"

    #include "libavutil/pixfmt.h"

    // MARK: - C Function
    static void sj_logShaderError(GLuint shader) {
     GLint info_len = 0;
     glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &amp;info_len);
     if (info_len == 0) NSLog(@"Empty info");
     else {
       GLchar *log = (GLchar *)malloc(info_len);
       glGetShaderInfoLog(shader, info_len, &amp;info_len, log);
       NSLog(@"Shader compile log: %s", log);
     }
    }

    static void sj_logProgramError(GLuint program) {
     int info_length;
     glGetProgramiv(program, GL_INFO_LOG_LENGTH, &amp;info_length);
     if (info_length) {
       GLchar *log = (GLchar *)malloc(info_length);
       glGetProgramInfoLog(program, info_length, &amp;info_length, log);
       NSLog(@"Program link log: %s", log);
     }
    }

    GLuint sj_loadShader(GLenum shader_type, const char* shader_source) {
     GLuint shader = glCreateShader(shader_type);
     glShaderSource(shader, 1, &amp;shader_source, NULL);
     glCompileShader(shader);
     GLint compile_status = 0;
     glGetShaderiv(shader, GL_COMPILE_STATUS, &amp;compile_status);
     if (!compile_status) goto fail;
     return shader;

    fail:
     if (shader) {
       sj_logShaderError(shader);
       glDeleteShader(shader);
     }
     return 0;
    }

    void loadOrtho(float *matrix, float left, float right, float bottom, float top, float near, float far) {
     float r_l = right - left;
     float t_b = top - bottom;
     float f_n = far - near;
     float tx = (right + left)/(right - left);
     float ty = (top + bottom)/(top - bottom);
     float tz = (far + near)/(far - near);

     matrix[0] = 2.0f / r_l;
     matrix[1] = 0.0f;
     matrix[2] = 0.0f;
     matrix[3] = 0.0f;

     matrix[4] = 0.0f;
     matrix[5] = 2.0f / t_b;
     matrix[6] = 0.0f;
     matrix[7] = 0.0f;

     matrix[8] = 0.0f;
     matrix[9] = 0.0f;
     matrix[10] = -2.0f / f_n;
     matrix[11] = 0.0f;

     matrix[12] = tx;
     matrix[13] = ty;
     matrix[14] = tz;
     matrix[15] = 1.0f;
    }


    // BT.709, standard for HDTV
    static const GLfloat g_bt709[] = {
     1.164,  1.164,  1.164,
     0.0,   -0.213,  2.112,
     1.793, -0.533,  0.0,
    };

    const GLfloat *getColorMatrix_bt709() {
     return g_bt709;
    }

    enum {
     ATTRIBUTE_VERTEX,
     ATTRIBUTE_TEXCOORD,
    };

    @implementation SJGLView {
     EAGLContext *_context;

     GLuint      _framebuffer;
     GLuint      _renderbuffer;
     GLint       _backingWidth;
     GLint       _backingHeight;
     GLfloat     _vertices[8];
     GLuint      _program;
     GLuint      _av4Position;
     GLuint      _av2Texcoord;
     GLuint      _um4Mvp;
     GLfloat     _texcoords[8];
     GLuint      _us2Sampler[3];
     GLuint      _um3ColorConversion;
     GLuint      _textures[3];

     SJDecoder *_decoder;
    }

    + (Class)layerClass {
     return [CAEAGLLayer class];
    }

    - (instancetype)initWithFrame:(CGRect)frame decoder:(SJDecoder *)decoder {
     self = [super initWithFrame:frame];
     if (self) {
       _decoder = decoder;
       [self setupGL];
     }
     return self;
    }

    - (void)layoutSubviews {
     glBindRenderbuffer(GL_RENDERBUFFER, _renderbuffer);
     [_context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer];
     glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &amp;_backingWidth);
     glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &amp;_backingHeight);

     [self updateVertices];
     [self render: nil];
    }

    - (void)setContentMode:(UIViewContentMode)contentMode
    {
     [super setContentMode:contentMode];
     [self updateVertices];

     [self render:nil];
    }


    - (void)setupGL {
     _context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
     NSAssert(_context != nil, @"Failed to init EAGLContext");

     CAEAGLLayer *eaglLayer= (CAEAGLLayer *)self.layer;
     eaglLayer.opaque = YES;
     eaglLayer.drawableProperties = @{
                                      kEAGLDrawablePropertyRetainedBacking: [NSNumber numberWithBool:YES],
                                      kEAGLDrawablePropertyColorFormat: kEAGLColorFormatRGBA8
                                      };

     [EAGLContext setCurrentContext:_context];
     if ([self setupEAGLContext]) {
       NSLog(@"Success to setup EAGLContext");
       if ([self loadShaders]) {
         NSLog(@"Success to load shader");
         _us2Sampler[0] = glGetUniformLocation(_program, "us2_SamplerX");
         _us2Sampler[1] = glGetUniformLocation(_program, "us2_SamplerY");
         _us2Sampler[2] = glGetUniformLocation(_program, "us2_SamplerZ");
         _um3ColorConversion = glGetUniformLocation(_program, "um3_ColorConversion");
       }
     }
    }

    - (BOOL)setupEAGLContext {
     glGenFramebuffers(1, &amp;_framebuffer);
     glGenRenderbuffers(1, &amp;_renderbuffer);
     glBindFramebuffer(GL_FRAMEBUFFER, _framebuffer);
     glBindRenderbuffer(GL_RENDERBUFFER, _renderbuffer);
     [_context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer *)self.layer];
     glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &amp;_backingWidth);
     glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &amp;_backingHeight);
     glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, _renderbuffer);

     GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
     if (status != GL_FRAMEBUFFER_COMPLETE) {
       NSLog(@"Failed to make complete framebuffer object: %x", status);
       return NO;
     }

     GLenum glError = glGetError();
     if (glError != GL_NO_ERROR) {
       NSLog(@"Failed to setup EAGLContext: %x", glError);
       return NO;
     }
     return YES;
    }

    - (BOOL)loadShaders {
     NSString *vertexPath = [[NSBundle mainBundle] pathForResource:@"vertex" ofType:@"vsh"];
     const char *vertexString = [[NSString stringWithContentsOfFile:vertexPath encoding:NSUTF8StringEncoding error:nil] UTF8String];

     NSString *fragmentPath = _decoder.format == SJVideoFrameFormatYUV ? [[NSBundle mainBundle] pathForResource:@"yuv420p" ofType:@"fsh"] :
     [[NSBundle mainBundle] pathForResource:@"rgb" ofType:@"fsh"];
     const char *fragmentString = [[NSString stringWithContentsOfFile:fragmentPath encoding:NSUTF8StringEncoding error:nil] UTF8String];

     GLuint vertexShader = sj_loadShader(GL_VERTEX_SHADER, vertexString);
     GLuint fragmentShader = sj_loadShader(GL_FRAGMENT_SHADER, fragmentString);

     _program = glCreateProgram();
     glAttachShader(_program, vertexShader);
     glAttachShader(_program, fragmentShader);
     glLinkProgram(_program);
     GLint link_status = GL_FALSE;
     glGetProgramiv(_program, GL_LINK_STATUS, &amp;link_status);
     if(!link_status) goto fail;

     _av4Position = glGetAttribLocation(_program, "av4_Position");
     _av2Texcoord = glGetAttribLocation(_program, "av2_Texcoord");
     _um4Mvp = glGetUniformLocation(_program, "um4_ModelViewProjection");
     return YES;
    fail:
     sj_logProgramError(_program);
     glDeleteShader(vertexShader);
     glDeleteShader(fragmentShader);
     glDeleteProgram(_program);
     return NO;
    }

    - (void)useRenderer {
     glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
     glUseProgram(_program);

     if (0 == _textures[0]) glGenTextures(3, _textures);
     for (int i = 0; i &lt; 3; i++) {
       glActiveTexture(GL_TEXTURE0 + i);
       glBindTexture(GL_TEXTURE_2D, _textures[i]);

       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
       glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
       glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

       glUniform1i(_us2Sampler[i], i);
     }
     glUniformMatrix3fv(_um3ColorConversion, 1, GL_FALSE, getColorMatrix_bt709());
    }

    - (void)uploadTexture:(SJVideoFrame *)frame {
     if (frame.format == SJVideoFrameFormatYUV) {
       SJVideoYUVFrame *yuvFrame = (SJVideoYUVFrame *)frame;
       const GLubyte *pixel[3] = { yuvFrame.luma.bytes, yuvFrame.chromaB.bytes, yuvFrame.chromaR.bytes };
       const GLsizei widths[3] = { yuvFrame.width, yuvFrame.width/2, yuvFrame.width/2 };
       const GLsizei heights[3] = { yuvFrame.height, yuvFrame.height/2, yuvFrame.height/2 };
       for (int i = 0; i &lt; 3; i++) {
         glBindTexture(GL_TEXTURE_2D, _textures[i]);
         glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, widths[i], heights[i], 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, pixel[i]);
       }
     }

    }

    - (void)render:(SJVideoFrame *)frame {
     [EAGLContext setCurrentContext:_context];
     glUseProgram(_program);
     [self useRenderer];
     GLfloat modelviewProj[16];
     loadOrtho(modelviewProj, -1.0f, 1.0f, -1.0f, 1.0f, -1.0f, 1.0f);
     glUniformMatrix4fv(_um4Mvp, 1, GL_FALSE, modelviewProj);
     [self updateVertices];
     [self updateTexcoords];

     glBindFramebuffer(GL_FRAMEBUFFER, _framebuffer);
     glViewport(0, 0, _backingWidth, _backingHeight);

     [self uploadTexture:frame];
     glClear(GL_COLOR_BUFFER_BIT);
     glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);

     glBindRenderbuffer(GL_RENDERBUFFER, _renderbuffer);
     [_context presentRenderbuffer:GL_RENDERBUFFER];
    }

    - (void)updateVertices {
     [self resetVertices];

     BOOL fit        = (self.contentMode == UIViewContentModeScaleAspectFit);
     float width     = _decoder.frameWidth;
     float height    = _decoder.frameHeight;
     const float dW  = (float)_backingWidth / width;
     const float dH  = (float)_backingHeight / height;
     float dd        = fit ? MIN(dH, dW) : MAX(dH, dW);
     float nW        = (width  * dd / (float)_backingWidth);
     float nH        = (height * dd / (float)_backingHeight);

     _vertices[0] = -nW;
     _vertices[1] = -nH;
     _vertices[2] =  nW;
     _vertices[3] = -nH;
     _vertices[4] = -nW;
     _vertices[5] =  nH;
     _vertices[6] =  nW;
     _vertices[7] =  nH;

     glVertexAttribPointer(_av4Position, 2, GL_FLOAT, GL_FALSE, 0, _vertices);
     glEnableVertexAttribArray(_av4Position);
    }

    - (void)resetVertices {
     _vertices[0] = -1.0f;
     _vertices[1] = -1.0f;
     _vertices[2] =  1.0f;
     _vertices[3] = -1.0f;
     _vertices[4] = -1.0f;
     _vertices[5] =  1.0f;
     _vertices[6] =  1.0f;
     _vertices[7] =  1.0f;
    }

    - (void)updateTexcoords {
     [self resetTexcoords];

     glVertexAttribPointer(_av2Texcoord, 2, GL_FLOAT, GL_FALSE, 0, _texcoords);
     glEnableVertexAttribArray(_av2Texcoord);
    }

    - (void)resetTexcoords {
     _texcoords[0] = 0.0f;
     _texcoords[1] = 1.0f;
     _texcoords[2] = 1.0f;
     _texcoords[3] = 1.0f;
     _texcoords[4] = 0.0f;
     _texcoords[5] = 0.0f;
     _texcoords[6] = 1.0f;
     _texcoords[7] = 0.0f;
    }

    .fsh :

    precision highp float;
    varying   highp vec2 vv2_Texcoord;
    uniform   mat3  um3_ColorConversion;
    uniform   lowp  sampler2D us2_SamplerX;
    uniform   lowp  sampler2D us2_SamplerY;
    uniform   lowp  sampler2D us2_SamplerZ;
    void main() {
     mediump vec3 yuv;
     lowp    vec3 rgb;
     yuv.x = (texture2D(us2_SamplerX, vv2_Texcoord).r - (16.0/255.0));
     yuv.y = (texture2D(us2_SamplerY, vv2_Texcoord).r - 0.5);
     yuv.z = (texture2D(us2_SamplerZ, vv2_Texcoord).r - 0.5);
     rgb = um3_ColorConversion * yuva;
     gl_FragColor = vec4(rgb, 1.0);
    }

    .vsh file :

    precision highp float;
    varying highp vec2 vv2_Texcoord;
    uniform lowp sampler2D us2_SamplerX;

    void main() {
     gl_FragColor = vec4(texture2D(us2_SamplerX, vv2_Texcoord).rgb, 1)
    }

    Result image :
    result

    The rgb image :
    RGB image

  • avfilter/vf_waveform : draw graticule for color filter too

    7 mars 2016, par Paul B Mahol
    avfilter/vf_waveform : draw graticule for color filter too
    

    Signed-off-by : Paul B Mahol <onemda@gmail.com>

    • [DH] libavfilter/vf_waveform.c