Recherche avancée

Sur d’autres sites (5907)

• Edge of text clipped a few pixels in ffmpeg

  18 mai 2024, par THEMOUNTAINSANDTHESKIES

  Trying to make a short video of a background image with text and some background audio. It's functional, but the right side of each line of my text is always clipped a few pixels. What am I missing ?

  


  Here's my python code (which includes the ffmpeg command) :

  


  font_size = 100
text='Example Text Example Text \n Example Text'
font_path = 'Bangers-Regular.ttf'
image_path = 'background.jpg'
audio_path = 'audio.wav'
duration = 15 #or whatever the audio's length is
output_path = 'output.mp4'

font_path_escaped = font_path.replace("\\", "\\\\\\\\").replace("C:", "C\\:")

lines = text.split('\n')
num_lines = len(lines)
line_height = font_size + 10
start_y = (1080 - line_height * num_lines) // 2

filter_complex = []
for i, line in enumerate(lines):
    y_position = start_y + i * line_height
    filter_complex.append(
        f"drawtext=text='{line}':fontfile='{font_path_escaped}':fontsize={font_size}:"
        f"x=((w-text_w)/2):y={y_position}:"
        "fontcolor=white:borderw=6:bordercolor=black"
    )

filter_complex_string = ','.join(filter_complex)

command = [
    'ffmpeg',
    '-loop', '1',
    '-i', image_path,
    '-i', audio_path,
    '-filter_complex', filter_complex_string,
    '-map', '[v]',
    '-map', '1:a',
    '-c:v', 'hevc_nvenc',
    '-c:a', 'aac',
    '-pix_fmt', 'yuv420p',
    '-t', str(duration),
    '-shortest',
    '-loglevel', 'debug',
    '-y',
    output_path
]


subprocess.run(command, check=True)
print(f"Video created successfully: {output_path}")


  


  and a frame from the outputted video :

  


  

  


• Decoded YUV shows green edge when rendered with OpenGL

  2 février 2023, par Alex

  Any idea, why decoded YUV -> RGB(shader conversion) has that extra green edge on the right side ?
  
Almost any 1080X1920 video seems to have this issue.

  


  

  


  A screen recording of the issue is uploaded here https://imgur.com/a/JtUZq4h

  


  Once I manually scale up the texture width, I can see it fills up to the viewport, but it would be nice if I could fix the actual cause. Is it some padding that's part of YUV colorspace ? What else could it be ?

  


  My model is -1 to 1, filling the entire width
  
The texture coordinates are also 0 to 1 ratio

  


  float vertices[] = {
    -1.0, 1.0f, 0.0f, 0.0,     // top left
     1.0f, 1.0f, 1.0, 0.0,      // top right
    -1.0f, -1.0f, 0.0f, 1.0f,  // bottom left
     1.0f, -1.0f, 1.0f, 1.0f    // bottom right
};


  


  Fragment Shader

  


  #version 330 core

in vec2 TexCoord;

out vec4 FragColor;
precision highp float;
uniform sampler2D textureY;
uniform sampler2D textureU;
uniform sampler2D textureV;
uniform float alpha;
uniform vec2 texScale;


void main()
{
    float y = texture(textureY, TexCoord / texScale).r;
    float u = texture(textureU, TexCoord / texScale).r - 0.5; 
    float v = texture(textureV, TexCoord / texScale).r - 0.5;
    
    vec3 rgb;
    
    //yuv - 709
    rgb.r = clamp(y + (1.402 * v), 0, 255);
    rgb.g = clamp(y - (0.2126 * 1.5748 / 0.7152) * u - (0.0722 * 1.8556 / 0.7152) * v, 0, 255);
    rgb.b = clamp(y + (1.8556 * u), 0,255);

    FragColor = vec4(rgb, 1.0);
} 


  


  Texture Class

  


  class VideoTexture {
   public:
    VideoTexture(Decoder *dec) : decoder(dec) {
        glGenTextures(1, &texture1);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glBindTexture(GL_TEXTURE_2D, texture1);
        glTexImage2D(GL_TEXTURE_2D, 0, internalFormat, decoder->frameQueue.first().linesize[0], decoder->frameQueue.first().height, 0, format, GL_UNSIGNED_BYTE, 0);
        glGenerateMipmap(GL_TEXTURE_2D);

        glGenTextures(1, &texture2);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glBindTexture(GL_TEXTURE_2D, texture2);
        glTexImage2D(GL_TEXTURE_2D, 0, internalFormat, decoder->frameQueue.first().linesize[1], decoder->frameQueue.first().height / 2, 0, format, GL_UNSIGNED_BYTE, 0);
        glGenerateMipmap(GL_TEXTURE_2D);

        glGenTextures(1, &texture3);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glBindTexture(GL_TEXTURE_2D, texture3);
        glTexImage2D(GL_TEXTURE_2D, 0, internalFormat, decoder->frameQueue.first().linesize[2], decoder->frameQueue.first().height / 2, 0, format, GL_UNSIGNED_BYTE, 0);
        glGenerateMipmap(GL_TEXTURE_2D);
    }

    void Render(Shader *shader, Gui *gui) {
        if (decoder->frameQueue.isEmpty()) {
            return;
        }

        glActiveTexture(GL_TEXTURE0);
        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, decoder->frameQueue.first().linesize[0], decoder->frameQueue.first().height, format, GL_UNSIGNED_BYTE, decoder->frameQueue.at(currentFrame).data[0]);
        glBindTexture(GL_TEXTURE_2D, texture1);
        shader->setInt("textureY", 0);

        glActiveTexture(GL_TEXTURE1);
        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, decoder->frameQueue.first().linesize[1], decoder->frameQueue.first().height / 2, format, GL_UNSIGNED_BYTE, decoder->frameQueue.at(currentFrame).data[1]);
        glBindTexture(GL_TEXTURE_2D, texture2);
        shader->setInt("textureU", 1);

        glActiveTexture(GL_TEXTURE2);
        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, decoder->frameQueue.first().linesize[2], decoder->frameQueue.first().height / 2, format, GL_UNSIGNED_BYTE, decoder->frameQueue.at(currentFrame).data[2]);
        glBindTexture(GL_TEXTURE_2D, texture3);
        shader->setInt("textureV", 2);
    }

    ~VideoTexture() {
        printf("\nVideo texture destructor");
        glDeleteTextures(1, &texture1);
        glDeleteTextures(1, &texture2);
        glDeleteTextures(1, &texture3);
    }

   private:
    GLuint texture1;
    GLuint texture2;
    GLuint texture3;
    GLint internalFormat = GL_RG8;
    GLint format = GL_RED;
    int currentFrame = 0;
    Decoder *decoder;
}


  


• Questions about license of ffmpeg in Android [on hold]

  23 décembre 2016, par Season

  I want to make an video editing app(may include advertisement or even earn money).

  And I found that ffmpeg is a great library for my app.

  And I can use it for compress video, trim video and change video format.

  The commands that the app may use :

  Reducing video size with same format and reducing frame size

  Cutting the videos based on start and end time using ffmpeg

  I found that ffmpeg is using LGPL and partially GPL licenses but I do not familiar with these two terms.

  What should I do so that I can use ffmpeg legally ?