• Definition: libavif is a library for encoding and decoding AVIF (AV1 Image File Format) images, which use the AV1 video codec for image compression.
• Function: Provides tools and APIs to encode, decode, and manipulate AVIF images, facilitating the use of this efficient image format in applications.
• Components:

   * '''Encoder''': Functions to encode images into the AVIF format.
   * '''Decoder''': Functions to decode AVIF images back into standard image formats.
   * '''Utilities''': Additional tools for manipulating and processing AVIF images.

• Features:

   * '''High Compression Efficiency''': Utilizes the AV1 codec to achieve high compression ratios while maintaining image quality.
   * '''Support for HDR''': Supports High Dynamic Range (HDR) imaging.
   * '''Lossy and Lossless Compression''': Offers both lossy and lossless compression options.
   * '''Metadata Handling''': Supports embedding and extraction of image metadata.

• Usage: Suitable for applications needing efficient image storage and transmission, such as web applications, photo storage services, and multimedia applications.

• Encoding an image to AVIF using libavif in C:

   ```c
   #include 
   #include 

 int main() {
     avifRWData raw = AVIF_DATA_EMPTY;
     avifImage *image = avifImageCreate(800, 600, 8, AVIF_PIXEL_FORMAT_YUV444);
     
     // Populate the image with pixel data
     // ...

     avifEncoder *encoder = avifEncoderCreate();
     avifResult result = avifEncoderWrite(encoder, image, &raw);
     if (result == AVIF_RESULT_OK) {
         FILE *f = fopen("output.avif", "wb");
         fwrite(raw.data, 1, raw.size, f);
         fclose(f);
     } else {
         fprintf(stderr, "Failed to encode image: %s\n", avifResultToString(result));
     }

     avifRWDataFree(&raw);
     avifEncoderDestroy(encoder);
     avifImageDestroy(image);
     return 0;
 }
 ```

• Decoding an AVIF image using libavif in C:

   ```c
   #include 
   #include 

 int main() {
     avifRWData raw = AVIF_DATA_EMPTY;
     FILE *f = fopen("input.avif", "rb");
     fseek(f, 0, SEEK_END);
     raw.size = ftell(f);
     fseek(f, 0, SEEK_SET);
     raw.data = (uint8_t *)malloc(raw.size);
     fread(raw.data, 1, raw.size, f);
     fclose(f);

     avifImage *image = avifImageCreateEmpty();
     avifDecoder *decoder = avifDecoderCreate();
     avifResult result = avifDecoderRead(decoder, image, &raw);
     if (result == AVIF_RESULT_OK) {
         printf("Image decoded successfully\n");
         // Process the image
     } else {
         fprintf(stderr, "Failed to decode image: %s\n", avifResultToString(result));
     }

     avifRWDataFree(&raw);
     avifDecoderDestroy(decoder);
     avifImageDestroy(image);
     return 0;
 }
 ```

• Using libavif in a Python script (with a hypothetical Python binding):

   ```python
   import libavif

 # Load an image and encode it to AVIF
 image = libavif.Image(width=800, height=600, depth=8)
 # Populate the image with pixel data
 # ...

 encoded_data = image.encode()
 with open("output.avif", "wb") as f:
     f.write(encoded_data)

 # Decode an AVIF image
 with open("input.avif", "rb") as f:
     encoded_data = f.read()

 decoded_image = libavif.Image.decode(encoded_data)
 print("Image decoded successfully")
 ```

• libavif: A library for encoding and decoding AVIF images, which utilize the AV1 codec for high compression efficiency and support both lossy and lossless compression. libavif supports HDR imaging and metadata handling, making it suitable for applications requiring efficient image storage and transmission.