chromium/media/capture/content/capture_resolution_chooser.h

// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_CAPTURE_CONTENT_CAPTURE_RESOLUTION_CHOOSER_H_
#define MEDIA_CAPTURE_CONTENT_CAPTURE_RESOLUTION_CHOOSER_H_

#include <vector>

#include "media/capture/capture_export.h"
#include "ui/gfx/geometry/size.h"

namespace media {

// Encapsulates the logic that determines the capture frame resolution based on:
//   1. The configured minimum/maximum frame resolution.
//   2. Whether the capture frame resolution must be of a fixed aspect ratio.
//   3. Changes to resolution of the source content.
//   4. Changes to the (externally-computed) target data volume, provided in
//      terms of the number of pixels in the frame.
//
// In variable-resolution use cases, the capture sizes are "snapped" to a small
// (i.e., usually less than a dozen) set of possibilities.  This is to prevent
// the end-to-end system from having to deal with rapidly-changing video frame
// resolutions that results from providing a fine-grained range of values.  The
// possible snapped frame sizes are computed relative to the resolution of the
// source content: They are the same or smaller in size, and are of the same
// aspect ratio.
class CAPTURE_EXPORT CaptureResolutionChooser { … };

}  // namespace media

#endif  // MEDIA_CAPTURE_CONTENT_CAPTURE_RESOLUTION_CHOOSER_H_