talk/session/phone/videocommon.cc

// libjingle
// Copyright 2010 Google Inc.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
//  1. Redistributions of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//  2. Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//  3. The name of the author may not be used to endorse or promote products
//     derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
// EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
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// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "talk/session/phone/videocommon.h"

#include <sstream>

#include "talk/base/common.h"

namespace cricket {

struct FourCCAliasEntry {
  uint32 alias;
  uint32 canonical;
};

static const FourCCAliasEntry kFourCCAliases[] = {
  {FOURCC_IYUV, FOURCC_I420},
  {FOURCC_YU12, FOURCC_I420},
  {FOURCC_YU16, FOURCC_I422},
  {FOURCC_YU24, FOURCC_I444},
  {FOURCC_YUYV, FOURCC_YUY2},
  {FOURCC_YUVS, FOURCC_YUY2},
  {FOURCC_HDYC, FOURCC_UYVY},
  {FOURCC_2VUY, FOURCC_UYVY},
  {FOURCC_BA81, FOURCC_BGGR},
  {FOURCC_JPEG, FOURCC_MJPG},  // Note: JPEG has DHT while MJPG does not.
  {FOURCC_DMB1, FOURCC_MJPG},
  {FOURCC_RGB3, FOURCC_RAW},
  {FOURCC_BGR3, FOURCC_24BG},
};

uint32 CanonicalFourCC(uint32 fourcc) {
  for (int i = 0; i < ARRAY_SIZE(kFourCCAliases); ++i) {
    if (kFourCCAliases[i].alias == fourcc) {
      return kFourCCAliases[i].canonical;
    }
  }
  // Not an alias, so return it as-is.
  return fourcc;
}

// The C++ standard requires a namespace-scope definition of static const
// integral types even when they are initialized in the declaration (see
// [class.static.data]/4), but MSVC with /Ze is non-conforming and treats that
// as a multiply defined symbol error (see
// http://msdn.microsoft.com/en-us/library/34h23df8.aspx).
#ifndef _MSC_EXTENSIONS
const int64 VideoFormat::kMinimumInterval;  // Initialized in header.
#endif

std::string VideoFormat::ToString() const {
  std::string fourcc_name = GetFourccName(fourcc) + " ";
  for (std::string::const_iterator i = fourcc_name.begin();
      i < fourcc_name.end(); ++i) {
    // Test character is printable; Avoid isprint() which asserts on negatives
    if (*i < 32 || *i >= 127) {
      fourcc_name = "";
      break;
    }
  }

  std::ostringstream ss;
  ss << fourcc_name << width << "x" << height << "x" << IntervalToFps(interval);
  return ss.str();
}

}  // namespace cricket