Trait exr::block::reader::ChunksReader

pub trait ChunksReader:
    Sized
    + Iterator<Item = Result<Chunk>>
    + ExactSizeIterator {
    // Required methods
    fn meta_data(&self) -> &MetaData;
    fn expected_chunk_count(&self) -> usize;

    // Provided methods
    fn headers(&self) -> &[Header] { ... }
    fn read_next_chunk(&mut self) -> Option<Result<Chunk>> { ... }
    fn on_progress<F>(self, on_progress: F) -> OnProgressChunksReader<Self, F> 
       where F: FnMut(f64) { ... }
    fn decompress_parallel(
        self,
        pedantic: bool,
        insert_block: impl FnMut(&MetaData, UncompressedBlock) -> UnitResult,
    ) -> UnitResult { ... }
    fn parallel_decompressor(
        self,
        pedantic: bool,
    ) -> Result<ParallelBlockDecompressor<Self>, Self> { ... }
    fn decompress_sequential(
        self,
        pedantic: bool,
        insert_block: impl FnMut(&MetaData, UncompressedBlock) -> UnitResult,
    ) -> UnitResult { ... }
    fn sequential_decompressor(
        self,
        pedantic: bool,
    ) -> SequentialBlockDecompressor<Self>  { ... }
}

Decode chunks in the file. The decoded chunks can be decompressed by calling decompress_parallel, decompress_sequential, or sequential_decompressor. Call on_progress to have a callback with each block. Also contains the image meta data.

Required Methods

fn meta_data(&self) -> &MetaData

The decoded exr meta data from the file.

fn expected_chunk_count(&self) -> usize

The number of chunks that this reader will return in total. Can be less than the total number of chunks in the file, if some chunks are skipped.

Provided Methods

fn headers(&self) -> &[Header]

The decoded exr headers from the file.

fn read_next_chunk(&mut self) -> Option<Result<Chunk>>

Read the next compressed chunk from the file. Equivalent to .next(), as this also is an iterator. Returns None if all chunks have been read.

fn on_progress<F>(self, on_progress: F) -> OnProgressChunksReader<Self, F>

where F: FnMut(f64),

Create a new reader that calls the provided progress callback for each chunk that is read from the file. If the file can be successfully decoded, the progress will always at least once include 0.0 at the start and 1.0 at the end.

fn decompress_parallel( self, pedantic: bool, insert_block: impl FnMut(&MetaData, UncompressedBlock) -> UnitResult, ) -> UnitResult

Decompress all blocks in the file, using multiple cpu cores, and call the supplied closure for each block. The order of the blocks is not deterministic. You can also use parallel_decompressor to obtain an iterator instead. Will fallback to sequential processing where threads are not available, or where it would not speed up the process.

fn parallel_decompressor( self, pedantic: bool, ) -> Result<ParallelBlockDecompressor<Self>, Self>

Return an iterator that decompresses the chunks with multiple threads. The order of the blocks is not deterministic. Use ParallelBlockDecompressor::new if you want to use your own thread pool. By default, this uses as many threads as there are CPUs. Returns the self if there is no need for parallel decompression.

fn decompress_sequential( self, pedantic: bool, insert_block: impl FnMut(&MetaData, UncompressedBlock) -> UnitResult, ) -> UnitResult

Return an iterator that decompresses the chunks in this thread. You can alternatively use sequential_decompressor if you prefer an external iterator.

fn sequential_decompressor( self, pedantic: bool, ) -> SequentialBlockDecompressor<Self>

Prepare reading the chunks sequentially, only a single thread, but with less memory overhead.

Object Safety

This trait is not object safe.

Implementors

impl<R, F> ChunksReader for OnProgressChunksReader<R, F>

where R: ChunksReader, F: FnMut(f64),

impl<R: Read + Seek> ChunksReader for AllChunksReader<R>

impl<R: Read + Seek> ChunksReader for FilteredChunksReader<R>