Class: Oil::JPEG

Inherits:

Object

• Object
• Oil::JPEG

Defined in:

ext/oil.c

Instance Method Summary

• #each(&block) ⇒ self

  Yields a series of binary strings that make up the resized JPEG image.

• #new(io, width, height) ⇒ Object constructor

  Creates a new resizer.

Constructor Details

#new(io, width, height) ⇒ Object

Creates a new resizer. io_in must be an IO-like object that responds to #read(size, buffer) and #seek(size).

The resulting image will be scaled to fit in the box given by width and height while preserving the original aspect ratio.

# File 'ext/oil.c', line 452

static VALUE
initialize(VALUE self, VALUE io, VALUE rb_width, VALUE rb_height)
{
    int width=FIX2INT(rb_width), height=FIX2INT(rb_height);
    struct thumbdata *data;
    
    if (width<1 || height<1) rb_raise(rb_eArgError, "Dimensions must be > 0");

    Data_Get_Struct(self, struct thumbdata, data);
    data->io = io;
    data->width = width;
    data->height = height;

    return self;
}

Instance Method Details

#each(&block) ⇒ self

Yields a series of binary strings that make up the resized JPEG image.

Returns:

• (self)

# File 'ext/oil.c', line 475

static VALUE
jpeg_each(VALUE self)
{
    struct jpeg_src src;
    struct jpeg_dest dest;
    struct thumbdata *data;
    Data_Get_Struct(self, struct thumbdata, data);

    memset(&src, 0, sizeof(struct jpeg_src));
    src.io = data->io;
    src.buffer = rb_str_new(0, 0);
    src.mgr.init_source = init_source;
    src.mgr.fill_input_buffer = fill_input_buffer;
    src.mgr.skip_input_data = skip_input_data;
    src.mgr.resync_to_restart = jpeg_resync_to_restart;
    src.mgr.term_source = term_source;

    memset(&dest, 0, sizeof(struct jpeg_dest));
    dest.buffer = rb_str_new(0, BUF_LEN);    
    dest.mgr.next_output_byte = RSTRING_PTR(dest.buffer);
    dest.mgr.free_in_buffer = BUF_LEN;
    dest.mgr.init_destination = init_destination;
    dest.mgr.empty_output_buffer = empty_output_buffer;
    dest.mgr.term_destination = term_destination;

    jpeg_each2(data, &src, &dest);

    return self;
}