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/*
* Copyright (c) 2010 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "media/base/video_common.h"
#include "api/array_view.h"
#include "rtc_base/arraysize.h"
#include "rtc_base/checks.h"
#include "rtc_base/strings/string_builder.h"
namespace cricket {
struct FourCCAliasEntry {
uint32_t alias;
uint32_t canonical;
};
static const FourCCAliasEntry kFourCCAliases[] = {
{FOURCC_IYUV, 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_JPEG, FOURCC_MJPG}, // Note: JPEG has DHT while MJPG does not.
{FOURCC_DMB1, FOURCC_MJPG},
{FOURCC_BA81, FOURCC_BGGR},
{FOURCC_RGB3, FOURCC_RAW},
{FOURCC_BGR3, FOURCC_24BG},
{FOURCC_CM32, FOURCC_BGRA},
{FOURCC_CM24, FOURCC_RAW},
};
uint32_t CanonicalFourCC(uint32_t fourcc) {
for (uint32_t i = 0; i < arraysize(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 Also:
#ifndef _MSC_EXTENSIONS
const int64_t 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;
}
}
char buf[256];
rtc::SimpleStringBuilder sb(buf);
sb << fourcc_name << width << "x" << height << "x"
<< IntervalToFpsFloat(interval);
return sb.str();
}
int GreatestCommonDivisor(int a, int b) {
RTC_DCHECK_GE(a, 0);
RTC_DCHECK_GT(b, 0);
int c = a % b;
while (c != 0) {
a = b;
b = c;
c = a % b;
}
return b;
}
int LeastCommonMultiple(int a, int b) {
RTC_DCHECK_GT(a, 0);
RTC_DCHECK_GT(b, 0);
return a * (b / GreatestCommonDivisor(a, b));
}
} // namespace cricket