dom/media/VideoUtils.cpp
author Jean-Yves Avenard <jyavenard@mozilla.com>
Wed, 06 Apr 2016 14:52:49 +1000
changeset 348786 aeb8153d296ac8512e7728afb797c25909125f1d
parent 341023 1114b55d0da25b717aa02c7a4d9fc9b0efb53bf1
child 348840 8124529fae831618e273940e55a4126c369c2bfc
child 349035 615f67ac2823f0428e54a64c42037c645076c39e
permissions -rw-r--r--
Bug 1248861: P11. Fix current downmixer. r?rillian Current downmixer was using vorbis channel order (which isn't surprising as it was extracted from the Ogg reader). Make it use SMPTE order as that's now what all MediaDataDecoder output. MozReview-Commit-ID: 5Kf7UnC52wL

/* 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 "VideoUtils.h"

#include "mozilla/Preferences.h"
#include "mozilla/Base64.h"
#include "mozilla/TaskQueue.h"
#include "mozilla/Telemetry.h"
#include "mozilla/Function.h"

#include "MediaResource.h"
#include "TimeUnits.h"
#include "nsMathUtils.h"
#include "nsSize.h"
#include "VorbisUtils.h"
#include "ImageContainer.h"
#include "mozilla/SharedThreadPool.h"
#include "nsIRandomGenerator.h"
#include "nsIServiceManager.h"
#include "nsServiceManagerUtils.h"
#include "nsIConsoleService.h"
#include "nsThreadUtils.h"
#include "nsCharSeparatedTokenizer.h"
#include "nsContentTypeParser.h"

#include <stdint.h>

namespace mozilla {

using layers::PlanarYCbCrImage;

static inline CheckedInt64 SaferMultDiv(int64_t aValue, uint32_t aMul, uint32_t aDiv) {
  int64_t major = aValue / aDiv;
  int64_t remainder = aValue % aDiv;
  return CheckedInt64(remainder) * aMul / aDiv + major * aMul;
}

// Converts from number of audio frames to microseconds, given the specified
// audio rate.
CheckedInt64 FramesToUsecs(int64_t aFrames, uint32_t aRate) {
  return SaferMultDiv(aFrames, USECS_PER_S, aRate);
}

media::TimeUnit FramesToTimeUnit(int64_t aFrames, uint32_t aRate) {
  int64_t major = aFrames / aRate;
  int64_t remainder = aFrames % aRate;
  return media::TimeUnit::FromMicroseconds(major) * USECS_PER_S +
    (media::TimeUnit::FromMicroseconds(remainder) * USECS_PER_S) / aRate;
}

// Converts from microseconds to number of audio frames, given the specified
// audio rate.
CheckedInt64 UsecsToFrames(int64_t aUsecs, uint32_t aRate) {
  return SaferMultDiv(aUsecs, aRate, USECS_PER_S);
}

// Format TimeUnit as number of frames at given rate.
CheckedInt64 TimeUnitToFrames(const media::TimeUnit& aTime, uint32_t aRate) {
  return UsecsToFrames(aTime.ToMicroseconds(), aRate);
}

nsresult SecondsToUsecs(double aSeconds, int64_t& aOutUsecs) {
  if (aSeconds * double(USECS_PER_S) > INT64_MAX) {
    return NS_ERROR_FAILURE;
  }
  aOutUsecs = int64_t(aSeconds * double(USECS_PER_S));
  return NS_OK;
}

static int32_t ConditionDimension(float aValue)
{
  // This will exclude NaNs and too-big values.
  if (aValue > 1.0 && aValue <= INT32_MAX)
    return int32_t(NS_round(aValue));
  return 0;
}

void ScaleDisplayByAspectRatio(nsIntSize& aDisplay, float aAspectRatio)
{
  if (aAspectRatio > 1.0) {
    // Increase the intrinsic width
    aDisplay.width = ConditionDimension(aAspectRatio * aDisplay.width);
  } else {
    // Increase the intrinsic height
    aDisplay.height = ConditionDimension(aDisplay.height / aAspectRatio);
  }
}

static int64_t BytesToTime(int64_t offset, int64_t length, int64_t durationUs) {
  NS_ASSERTION(length > 0, "Must have positive length");
  double r = double(offset) / double(length);
  if (r > 1.0)
    r = 1.0;
  return int64_t(double(durationUs) * r);
}

media::TimeIntervals GetEstimatedBufferedTimeRanges(mozilla::MediaResource* aStream,
                                                    int64_t aDurationUsecs)
{
  media::TimeIntervals buffered;
  // Nothing to cache if the media takes 0us to play.
  if (aDurationUsecs <= 0 || !aStream)
    return buffered;

  // Special case completely cached files.  This also handles local files.
  if (aStream->IsDataCachedToEndOfResource(0)) {
    buffered +=
      media::TimeInterval(media::TimeUnit::FromMicroseconds(0),
                          media::TimeUnit::FromMicroseconds(aDurationUsecs));
    return buffered;
  }

  int64_t totalBytes = aStream->GetLength();

  // If we can't determine the total size, pretend that we have nothing
  // buffered. This will put us in a state of eternally-low-on-undecoded-data
  // which is not great, but about the best we can do.
  if (totalBytes <= 0)
    return buffered;

  int64_t startOffset = aStream->GetNextCachedData(0);
  while (startOffset >= 0) {
    int64_t endOffset = aStream->GetCachedDataEnd(startOffset);
    // Bytes [startOffset..endOffset] are cached.
    NS_ASSERTION(startOffset >= 0, "Integer underflow in GetBuffered");
    NS_ASSERTION(endOffset >= 0, "Integer underflow in GetBuffered");

    int64_t startUs = BytesToTime(startOffset, totalBytes, aDurationUsecs);
    int64_t endUs = BytesToTime(endOffset, totalBytes, aDurationUsecs);
    if (startUs != endUs) {
      buffered +=
        media::TimeInterval(media::TimeUnit::FromMicroseconds(startUs),

                              media::TimeUnit::FromMicroseconds(endUs));
    }
    startOffset = aStream->GetNextCachedData(endOffset);
  }
  return buffered;
}

int DownmixAudioToStereo(mozilla::AudioDataValue* buffer,
                         int channels, uint32_t frames)
{
  int outChannels;
  outChannels = 2;
#ifdef MOZ_SAMPLE_TYPE_FLOAT32
  // Downmix matrix. Per-row normalization 1 for rows 3,4 and 2 for rows 5-8.
  static const float dmatrix[6][8][2]= {
      /*3*/{{0.5858f,0},{0,0.5858f},{0.4142f,0.4142f}},
      /*4*/{{0.4226f,0},{0,0.4226f},{0.366f, 0.2114f},{0.2114f,0.366f}},
      /*5*/{{0.6510f,0},{0,0.6510f},{0.4600f,0.4600f},{0.5636f,0.3254f},{0.3254f,0.5636f}},
      /*6*/{{0.5290f,0},{0,0.5290f},{0.3741f,0.3741f},{0.3741f,0.3741f},{0.4582f,0.2645f},{0.2645f,0.4582f}},
      /*7*/{{0.4553f,0},{0,0.4553f},{0.3220f,0.3220f},{0.3220f,0.3220f},{0.2788f,0.2788f},{0.3943f,0.2277f},{0.2277f,0.3943f}},
      /*8*/{{0.3886f,0},{0,0.3886f},{0.2748f,0.2748f},{0.2748f,0.2748f},{0.3366f,0.1943f},{0.1943f,0.3366f},{0.3366f,0.1943f},{0.1943f,0.3366f}},
  };
  // Re-write the buffer with downmixed data
  for (uint32_t i = 0; i < frames; i++) {
    float sampL = 0.0;
    float sampR = 0.0;
    for (int j = 0; j < channels; j++) {
      sampL+=buffer[i*channels+j]*dmatrix[channels-3][j][0];
      sampR+=buffer[i*channels+j]*dmatrix[channels-3][j][1];
    }
    buffer[i*outChannels]=sampL;
    buffer[i*outChannels+1]=sampR;
  }
#else
  // Downmix matrix. Per-row normalization 1 for rows 3,4 and 2 for rows 5-8.
  // Coefficients in Q14.
  static const int16_t dmatrix[6][8][2]= {
      /*3*/{{9598, 0},{0,   9598},{6786,6786}},
      /*4*/{{6925, 0},{0,   6925},{5997,3462},{3462,5997}},
      /*5*/{{10663,0},{0,  10663},{7540,7540},{9234,5331},{5331,9234}},
      /*6*/{{8668, 0},{0,   8668},{6129,6129},{6129,6129},{7507,4335},{4335,7507}},
      /*7*/{{7459, 0},{0,   7459},{5275,5275},{5275,5275},{4568,4568},{6460,3731},{3731,6460}},
      /*8*/{{6368, 0},{0,   6368},{4502,4502},{4502,4502},{5514,3184},{3184,5514},{5514,3184},{3184,5514}}
  };
  // Re-write the buffer with downmixed data
  for (uint32_t i = 0; i < frames; i++) {
    int32_t sampL = 0;
    int32_t sampR = 0;
    for (int j = 0; j < channels; j++) {
      sampL+=buffer[i*channels+j]*dmatrix[channels-3][j][0];
      sampR+=buffer[i*channels+j]*dmatrix[channels-3][j][1];
    }
    sampL = (sampL + 8192)>>14;
    buffer[i*outChannels] = static_cast<mozilla::AudioDataValue>(MOZ_CLIP_TO_15(sampL));
    sampR = (sampR + 8192)>>14;
    buffer[i*outChannels+1] = static_cast<mozilla::AudioDataValue>(MOZ_CLIP_TO_15(sampR));
  }
#endif
  return outChannels;
}

void DownmixStereoToMono(mozilla::AudioDataValue* aBuffer,
                         uint32_t aFrames)
{
  MOZ_ASSERT(aBuffer);
  const int channels = 2;
  for (uint32_t fIdx = 0; fIdx < aFrames; ++fIdx) {
#ifdef MOZ_SAMPLE_TYPE_FLOAT32
    float sample = 0.0;
#else
    int sample = 0;
#endif
    // The sample of the buffer would be interleaved.
    sample = (aBuffer[fIdx*channels] + aBuffer[fIdx*channels + 1]) * 0.5;
    aBuffer[fIdx*channels] = aBuffer[fIdx*channels + 1] = sample;
  }
}

bool
IsVideoContentType(const nsCString& aContentType)
{
  NS_NAMED_LITERAL_CSTRING(video, "video");
  if (FindInReadable(video, aContentType)) {
    return true;
  }
  return false;
}

bool
IsValidVideoRegion(const nsIntSize& aFrame, const nsIntRect& aPicture,
                   const nsIntSize& aDisplay)
{
  return
    aFrame.width <= PlanarYCbCrImage::MAX_DIMENSION &&
    aFrame.height <= PlanarYCbCrImage::MAX_DIMENSION &&
    aFrame.width * aFrame.height <= MAX_VIDEO_WIDTH * MAX_VIDEO_HEIGHT &&
    aFrame.width * aFrame.height != 0 &&
    aPicture.width <= PlanarYCbCrImage::MAX_DIMENSION &&
    aPicture.x < PlanarYCbCrImage::MAX_DIMENSION &&
    aPicture.x + aPicture.width < PlanarYCbCrImage::MAX_DIMENSION &&
    aPicture.height <= PlanarYCbCrImage::MAX_DIMENSION &&
    aPicture.y < PlanarYCbCrImage::MAX_DIMENSION &&
    aPicture.y + aPicture.height < PlanarYCbCrImage::MAX_DIMENSION &&
    aPicture.width * aPicture.height <= MAX_VIDEO_WIDTH * MAX_VIDEO_HEIGHT &&
    aPicture.width * aPicture.height != 0 &&
    aDisplay.width <= PlanarYCbCrImage::MAX_DIMENSION &&
    aDisplay.height <= PlanarYCbCrImage::MAX_DIMENSION &&
    aDisplay.width * aDisplay.height <= MAX_VIDEO_WIDTH * MAX_VIDEO_HEIGHT &&
    aDisplay.width * aDisplay.height != 0;
}

already_AddRefed<SharedThreadPool> GetMediaThreadPool(MediaThreadType aType)
{
  const char *name;
  switch (aType) {
    case MediaThreadType::PLATFORM_DECODER:
      name = "MediaPDecoder";
      break;
    default:
      MOZ_FALLTHROUGH_ASSERT("Unexpected MediaThreadType");
    case MediaThreadType::PLAYBACK:
      name = "MediaPlayback";
      break;
  }
  return SharedThreadPool::
    Get(nsDependentCString(name),
        Preferences::GetUint("media.num-decode-threads", 12));
}

bool
ExtractH264CodecDetails(const nsAString& aCodec,
                        int16_t& aProfile,
                        int16_t& aLevel)
{
  // H.264 codecs parameters have a type defined as avcN.PPCCLL, where
  // N = avc type. avc3 is avcc with SPS & PPS implicit (within stream)
  // PP = profile_idc, CC = constraint_set flags, LL = level_idc.
  // We ignore the constraint_set flags, as it's not clear from any
  // documentation what constraints the platform decoders support.
  // See http://blog.pearce.org.nz/2013/11/what-does-h264avc1-codecs-parameters.html
  // for more details.
  if (aCodec.Length() != strlen("avc1.PPCCLL")) {
    return false;
  }

  // Verify the codec starts with "avc1." or "avc3.".
  const nsAString& sample = Substring(aCodec, 0, 5);
  if (!sample.EqualsASCII("avc1.") && !sample.EqualsASCII("avc3.")) {
    return false;
  }

  // Extract the profile_idc and level_idc.
  nsresult rv = NS_OK;
  aProfile = PromiseFlatString(Substring(aCodec, 5, 2)).ToInteger(&rv, 16);
  NS_ENSURE_SUCCESS(rv, false);

  aLevel = PromiseFlatString(Substring(aCodec, 9, 2)).ToInteger(&rv, 16);
  NS_ENSURE_SUCCESS(rv, false);

  if (aLevel == 9) {
    aLevel = H264_LEVEL_1_b;
  } else if (aLevel <= 5) {
    aLevel *= 10;
  }

  // Capture the constraint_set flag value for the purpose of Telemetry.
  // We don't NS_ENSURE_SUCCESS here because ExtractH264CodecDetails doesn't
  // care about this, but we make sure constraints is above 4 (constraint_set5_flag)
  // otherwise collect 0 for unknown.
  uint8_t constraints = PromiseFlatString(Substring(aCodec, 7, 2)).ToInteger(&rv, 16);
  Telemetry::Accumulate(Telemetry::VIDEO_CANPLAYTYPE_H264_CONSTRAINT_SET_FLAG,
                        constraints >= 4 ? constraints : 0);

  // 244 is the highest meaningful profile value (High 4:4:4 Intra Profile)
  // that can be represented as single hex byte, otherwise collect 0 for unknown.
  Telemetry::Accumulate(Telemetry::VIDEO_CANPLAYTYPE_H264_PROFILE,
                        aProfile <= 244 ? aProfile : 0);

  // Make sure aLevel represents a value between levels 1 and 5.2,
  // otherwise collect 0 for unknown.
  Telemetry::Accumulate(Telemetry::VIDEO_CANPLAYTYPE_H264_LEVEL,
                        (aLevel >= 10 && aLevel <= 52) ? aLevel : 0);

  return true;
}

nsresult
GenerateRandomName(nsCString& aOutSalt, uint32_t aLength)
{
  nsresult rv;
  nsCOMPtr<nsIRandomGenerator> rg =
    do_GetService("@mozilla.org/security/random-generator;1", &rv);
  if (NS_FAILED(rv)) return rv;

  // For each three bytes of random data we will get four bytes of ASCII.
  const uint32_t requiredBytesLength =
    static_cast<uint32_t>((aLength + 3) / 4 * 3);

  uint8_t* buffer;
  rv = rg->GenerateRandomBytes(requiredBytesLength, &buffer);
  if (NS_FAILED(rv)) return rv;

  nsAutoCString temp;
  nsDependentCSubstring randomData(reinterpret_cast<const char*>(buffer),
                                   requiredBytesLength);
  rv = Base64Encode(randomData, temp);
  free(buffer);
  buffer = nullptr;
  if (NS_FAILED (rv)) return rv;

  aOutSalt = temp;
  return NS_OK;
}

nsresult
GenerateRandomPathName(nsCString& aOutSalt, uint32_t aLength)
{
  nsresult rv = GenerateRandomName(aOutSalt, aLength);
  if (NS_FAILED(rv)) return rv;

  // Base64 characters are alphanumeric (a-zA-Z0-9) and '+' and '/', so we need
  // to replace illegal characters -- notably '/'
  aOutSalt.ReplaceChar(FILE_PATH_SEPARATOR FILE_ILLEGAL_CHARACTERS, '_');
  return NS_OK;
}

already_AddRefed<TaskQueue>
CreateMediaDecodeTaskQueue()
{
  RefPtr<TaskQueue> queue = new TaskQueue(
    GetMediaThreadPool(MediaThreadType::PLATFORM_DECODER));
  return queue.forget();
}

already_AddRefed<FlushableTaskQueue>
CreateFlushableMediaDecodeTaskQueue()
{
  RefPtr<FlushableTaskQueue> queue = new FlushableTaskQueue(
    GetMediaThreadPool(MediaThreadType::PLATFORM_DECODER));
  return queue.forget();
}

void
SimpleTimer::Cancel() {
  if (mTimer) {
#ifdef DEBUG
    nsCOMPtr<nsIEventTarget> target;
    mTimer->GetTarget(getter_AddRefs(target));
    nsCOMPtr<nsIThread> thread(do_QueryInterface(target));
    MOZ_ASSERT(NS_GetCurrentThread() == thread);
#endif
    mTimer->Cancel();
    mTimer = nullptr;
  }
  mTask = nullptr;
}

NS_IMETHODIMP
SimpleTimer::Notify(nsITimer *timer) {
  RefPtr<SimpleTimer> deathGrip(this);
  if (mTask) {
    mTask->Run();
    mTask = nullptr;
  }
  return NS_OK;
}

nsresult
SimpleTimer::Init(nsIRunnable* aTask, uint32_t aTimeoutMs, nsIThread* aTarget)
{
  nsresult rv;

  // Get target thread first, so we don't have to cancel the timer if it fails.
  nsCOMPtr<nsIThread> target;
  if (aTarget) {
    target = aTarget;
  } else {
    rv = NS_GetMainThread(getter_AddRefs(target));
    if (NS_FAILED(rv)) {
      return rv;
    }
  }

  nsCOMPtr<nsITimer> timer = do_CreateInstance(NS_TIMER_CONTRACTID, &rv);
  if (NS_FAILED(rv)) {
    return rv;
  }
  // Note: set target before InitWithCallback in case the timer fires before
  // we change the event target.
  rv = timer->SetTarget(aTarget);
  if (NS_FAILED(rv)) {
    timer->Cancel();
    return rv;
  }
  rv = timer->InitWithCallback(this, aTimeoutMs, nsITimer::TYPE_ONE_SHOT);
  if (NS_FAILED(rv)) {
    return rv;
  }

  mTimer = timer.forget();
  mTask = aTask;
  return NS_OK;
}

NS_IMPL_ISUPPORTS(SimpleTimer, nsITimerCallback)

already_AddRefed<SimpleTimer>
SimpleTimer::Create(nsIRunnable* aTask, uint32_t aTimeoutMs, nsIThread* aTarget)
{
  RefPtr<SimpleTimer> t(new SimpleTimer());
  if (NS_FAILED(t->Init(aTask, aTimeoutMs, aTarget))) {
    return nullptr;
  }
  return t.forget();
}

void
LogToBrowserConsole(const nsAString& aMsg)
{
  if (!NS_IsMainThread()) {
    nsString msg(aMsg);
    nsCOMPtr<nsIRunnable> task =
      NS_NewRunnableFunction([msg]() { LogToBrowserConsole(msg); });
    NS_DispatchToMainThread(task.forget(), NS_DISPATCH_NORMAL);
    return;
  }
  nsCOMPtr<nsIConsoleService> console(
    do_GetService("@mozilla.org/consoleservice;1"));
  if (!console) {
    NS_WARNING("Failed to log message to console.");
    return;
  }
  nsAutoString msg(aMsg);
  console->LogStringMessage(msg.get());
}

bool
IsAACCodecString(const nsAString& aCodec)
{
  return
    aCodec.EqualsLiteral("mp4a.40.2") || // MPEG4 AAC-LC
    aCodec.EqualsLiteral("mp4a.40.5") || // MPEG4 HE-AAC
    aCodec.EqualsLiteral("mp4a.67")   || // MPEG2 AAC-LC
    aCodec.EqualsLiteral("mp4a.40.29");  // MPEG4 HE-AACv2
}

bool
ParseCodecsString(const nsAString& aCodecs, nsTArray<nsString>& aOutCodecs)
{
  aOutCodecs.Clear();
  bool expectMoreTokens = false;
  nsCharSeparatedTokenizer tokenizer(aCodecs, ',');
  while (tokenizer.hasMoreTokens()) {
    const nsSubstring& token = tokenizer.nextToken();
    expectMoreTokens = tokenizer.separatorAfterCurrentToken();
    aOutCodecs.AppendElement(token);
  }
  if (expectMoreTokens) {
    // Last codec name was empty
    return false;
  }
  return true;
}

static bool
CheckContentType(const nsAString& aContentType,
                 mozilla::function<bool(const nsAString&)> aSubtypeFilter,
                 mozilla::function<bool(const nsAString&)> aCodecFilter)
{
  nsContentTypeParser parser(aContentType);
  nsAutoString mimeType;
  nsresult rv = parser.GetType(mimeType);
  if (NS_FAILED(rv) || !aSubtypeFilter(mimeType)) {
    return false;
  }

  nsString codecsStr;
  parser.GetParameter("codecs", codecsStr);
  nsTArray<nsString> codecs;
  if (!ParseCodecsString(codecsStr, codecs)) {
    return false;
  }
  for (const nsString& codec : codecs) {
    if (!aCodecFilter(codec)) {
      return false;
    }
  }
  return true;
}

bool
IsH264ContentType(const nsAString& aContentType)
{
  return CheckContentType(aContentType,
    [](const nsAString& type) {
      return type.EqualsLiteral("video/mp4");
    },
    [](const nsAString& codec) {
      int16_t profile = 0;
      int16_t level = 0;
      return ExtractH264CodecDetails(codec, profile, level);
    }
  );
}

bool
IsAACContentType(const nsAString& aContentType)
{
  return CheckContentType(aContentType,
    [](const nsAString& type) {
      return type.EqualsLiteral("audio/mp4") ||
             type.EqualsLiteral("audio/x-m4a");
    },
    [](const nsAString& codec) {
      return codec.EqualsLiteral("mp4a.40.2") || // MPEG4 AAC-LC
             codec.EqualsLiteral("mp4a.40.5") || // MPEG4 HE-AAC
             codec.EqualsLiteral("mp4a.67");     // MPEG2 AAC-LC
    });
}

} // end namespace mozilla