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I have a requirement where i need to load a sequence of images to the memory and than play them back to back.

I load all of the files into a std::vector and after they all get loaded i play them.

this is code for loading each file.

void loadTextureFromFile(const GLchar *file)
{
    // Create Texture object
    Texture2D texture;
    // Load image
    int width, height, channels;
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    unsigned char* image = SOIL_load_image(file, &width, &height, &channels, SOIL_LOAD_AUTO);
    // Set The Internal Format
    if (channels > 3)
    {
        texture.Internal_Format = GL_RGBA;
        texture.Image_Format = GL_RGBA;
    }
    else
    {
        texture.Internal_Format = GL_RGB;
        texture.Image_Format = GL_RGB;
    }
    // Now generate texture
    texture.Generate(width, height, image);
    imageSequence.push_back(texture);
    // And finally free image data
    SOIL_free_image_data(image);
}

////////////////////////////////////////////////////////

Texture2D::Texture2D()
    : Width(0), Height(0), Internal_Format(GL_RGB), Image_Format(GL_RGB), Wrap_S(GL_REPEAT), Wrap_T(GL_REPEAT), Filter_Min(GL_LINEAR), Filter_Max(GL_LINEAR) , WrapMode(SumTextureDecl::TextureWrapMode::Repeat)
{
    glGenTextures(1, &this->ID);
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

//////////////////////////////////////////////////////

void Texture2D::Generate(GLuint width, GLuint height, unsigned char* data)
{
    float aniso = 0.0f;
    this->Width = width;
    this->Height = height;  

    glBindTexture(GL_TEXTURE_2D, this->ID);
    // Set Texture wrap and filter modes
    glGetFloatv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &aniso);     
    // Create Texture   
    glTexImage2D(GL_TEXTURE_2D, 0, this->Internal_Format, width, height, 0, this->Image_Format, GL_UNSIGNED_BYTE, data);
    glGenerateMipmap(GL_TEXTURE_2D);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, this->Wrap_S);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, this->Wrap_T);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, aniso);
    // Unbind texture
    glBindTexture(GL_TEXTURE_2D, 0);
}

it takes some time to load all the files of image sequence so what file format would load the fastest ?

I am using soil to load images by using some other library would the loading become more fast ?

Summit
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    Why don't you re-encode the images into each of the formats supported by your library and see which is faster? Then try other libraries (asking for libraries is off-topic on SO). In your case it sounds you'll benefit the most by loading the images asynchronously while the first ones are being displayed. – Yakov Galka Feb 08 '20 at 05:23
  • @ybungalobill i am currently loading the images which the library supports (png) , just wanted to check if by using a certain image format the loading becomes much faster. – Summit Feb 08 '20 at 05:26
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    The 'fastest' format is going to depend on the hardware. A simple format will require less CPU processing to decode but will generally have larger files and thus be IO (disk performance) bound. A highly compressed jpeg could be very small on disk but require a lot of CPU time to decode and thus be CPU bound. You need to profile the various options available. – G.M. Feb 08 '20 at 09:23
  • @G.M could you please shed more light on this with examples of different file formats ? – Summit Feb 08 '20 at 09:26
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    That's basic research you need to do yourself. Have a look at the [documentation for SOIL](http://www.lonesock.net/soil.html) and check its supported formats. – G.M. Feb 08 '20 at 09:38

0 Answers0