image/imgIEncoder.idl
author Ryan VanderMeulen <ryanvm@gmail.com>
Wed, 17 Jan 2018 15:55:38 -0500
changeset 399709 ef04f3ad847540c876c130b7d140a960d922a024
parent 242578 ef516c84ef5496c3a8576e85c3e6ecb7b0776104
permissions -rw-r--r--
Backed out 20 changesets (bug 1411654) for incorrect android:debuggable. r=nalexander, a=RyanVM Backed out changeset cfad693be918 (bug 1411654) Backed out changeset 55776829a744 (bug 1411654) Backed out changeset c5bf85d56fed (bug 1411654) Backed out changeset c270f97bb0da (bug 1411654) Backed out changeset fde9bf9c14c3 (bug 1411654) Backed out changeset 01836fd98c63 (bug 1411654) Backed out changeset 730a70767743 (bug 1411654) Backed out changeset 690e265c684c (bug 1411654) Backed out changeset f918500d9cf5 (bug 1411654) Backed out changeset cec2b8828cc8 (bug 1411654) Backed out changeset 76085ddd5ac7 (bug 1411654) Backed out changeset 2b37201606f5 (bug 1411654) Backed out changeset d0d513d1c379 (bug 1411654) Backed out changeset e7b0cc801cf1 (bug 1411654) Backed out changeset 901b304603d9 (bug 1411654) Backed out changeset 373c9a71d945 (bug 1411654) Backed out changeset 3dc3beab95f8 (bug 1411654) Backed out changeset 22a861db1573 (bug 1411654) Backed out changeset 0850b319efd4 (bug 1411654) Backed out changeset d276d3deba05 (bug 1411654)

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"
#include "nsIAsyncInputStream.idl"
#include "nsIEventTarget.idl"

/**
 * imgIEncoder interface
 */
[scriptable, uuid(4baa2d6e-fee7-42df-ae3f-5fbebc0c267c)]
interface imgIEncoder : nsIAsyncInputStream
{
  // Possible values for outputOptions. Multiple values are semicolon-separated.
  //
  // PNG:
  // ----
  // transparency=[yes|no|none]  --  default: "yes"
  //     Overrides default from input format. "no" and "none" are equivalent.
  //
  //
  // APNG:
  // -----
  // The following options can be used with startImageEncode():
  //
  // transparency=[yes|no|none]  --  default: "yes"
  //     Overrides default from input format. "no" and "none" are equivalent.
  // skipfirstframe=[yes|no]  --  default: "no"
  //     Controls display of the first frame in animations. PNG-only clients
  //     always display the first frame (and only that frame).
  // frames=#  --  default: "1"
  //     Total number of frames in the image. The first frame, even if skipped,
  //     is always included in the count.
  // plays=#  --  default: "0"
  //     Number of times to play the animation sequence. "0" will repeat
  //     forever.
  //
  // The following options can be used for each frame, with addImageFrame():
  //
  // transparency=[yes|no|none]  --  default: "yes"
  //     Overrides default from input format. "no" and "none" are equivalent.
  // delay=#  --  default: "500"
  //     Number of milliseconds to display the frame, before moving to the next
  //     frame.
  // dispose=[none|background|previous]  --  default: "none"
  //     What to do with the image's canvas before rendering the next frame.
  //     See APNG spec.
  // blend=[source|over]  --  default: "source"
  //     How to render the new frame on the canvas. See APNG spec.
  // xoffset=#  --  default: "0"
  // yoffset=#  --  default: "0"
  //     Where to draw the frame, relative to the canvas.
  //
  //
  // JPEG:
  // -----
  //
  // quality=#  --  default: "92"
  //    Quality of compression, 0-100 (worst-best).
  //    Quality >= 90 prevents down-sampling of the color channels.


  // Possible values for input format (note that not all image formats
  // support saving alpha channels):

    // Input is RGB each pixel is represented by three bytes:
    // R, G, and B (in that order, regardless of host endianness)
  const uint32_t INPUT_FORMAT_RGB = 0;

    // Input is RGB each pixel is represented by four bytes:
    // R, G, and B (in that order, regardless of host endianness).
    // POST-MULTIPLIED alpha us used (50% transparent red is 0xff000080)
  const uint32_t INPUT_FORMAT_RGBA = 1;

    // Input is host-endian ARGB: On big-endian machines each pixel is therefore
    // ARGB, and for little-endian machiens (Intel) each pixel is BGRA
    // (This is used by canvas to match it's internal representation)
    //
    // PRE-MULTIPLIED alpha is used (That is, 50% transparent red is 0x80800000,
    // not 0x80ff0000
  const uint32_t INPUT_FORMAT_HOSTARGB = 2;

  /* data - list of bytes in the format specified by inputFormat
   * width  - width in pixels
   * height - height in pixels
   * stride - number of bytes per row in the image
   *          Normally (width*3) or (width*4), depending on your input format,
   *          but some data uses padding at the end of each row, which would
   *          be extra.
   * inputFormat - one of INPUT_FORMAT_* specifying the format of data
   * outputOptions - semicolon-delimited list of name=value pairs that can
   *                 give options to the output encoder. Options are encoder-
   *                 specific. Just give empty string for default behavior.
   */
  void initFromData([array, size_is(length), const] in uint8_t data,
                    in unsigned long length,
                    in uint32_t width,
                    in uint32_t height,
                    in uint32_t stride,
                    in uint32_t inputFormat,
                    in AString outputOptions);

  /*
   * For encoding images which may contain multiple frames, the 1-shot
   * initFromData() interface is too simplistic. The alternative is to
   * use startImageEncode(), call addImageFrame() one or more times, and
   * then finish initialization with endImageEncode().
   *
   * The arguments are basically the same as in initFromData().
   */
  void startImageEncode(in uint32_t width,
                    in uint32_t height,
                    in uint32_t inputFormat,
                    in AString outputOptions);

  void addImageFrame( [array, size_is(length), const] in uint8_t data,
                    in unsigned long length,
                    in uint32_t width,
                    in uint32_t height,
                    in uint32_t stride,
                    in uint32_t frameFormat,
                    in AString frameOptions);

  void endImageEncode();

  /*
   * Sometimes an encoder can contain another encoder and direct access
   * to its buffer is necessary.   It is only safe to assume that the buffer
   * returned from getImageBuffer() is of size equal to getImageBufferUsed().
   */
  [noscript] unsigned long getImageBufferUsed();
  [noscript] charPtr getImageBuffer();
};