Update to 2012_05_11 version.

Fixes:
- Don't throw error for invalid bitrate but limit to functional value
- More robust ASC parsing
- More robust handling of corrupt bitstreams
- Handle multiple raw access units

Change-Id: Ib49fe2545ff4185fe924126da702fe84ac5c2d87

5 files changed, 252 insertions, 71 deletions

diff --git a/libAACenc/src/aacenc.cpp b/libAACenc/src/aacenc.cpp
index 5ab7192..c2c744f 100644
--- a/libAACenc/src/aacenc.cpp
+++ b/libAACenc/src/aacenc.cpp
@@ -43,48 +43,61 @@
 
 
 
+#define MIN_BUFSIZE_PER_EFF_CHAN 6144
+
 static AAC_ENCODER_ERROR FDKaacEnc_InitCheckAncillary(INT bitRate,
                                                       INT framelength,
                                                       INT ancillaryRate,
                                                       INT *ancillaryBitsPerFrame,
                                                       INT sampleRate);
 
-/**
- * For calculating average bitrate of an access unit 32 bit data width is not sufficient
- * in worst case. Therefore use scaling of the samplingrate parameter to keep complete information.
- */
-typedef struct {
-    INT   samplingRate;
-    UCHAR scalingFactor;
-} SR_SCALING_TAB;
-
-static const SR_SCALING_TAB samplingRateScalingTable[] =
+INT FDKaacEnc_LimitBitrate(
+        HANDLE_TRANSPORTENC hTpEnc,
+        INT coreSamplingRate,
+        INT frameLength,
+        INT nChannels,
+        INT nChannelsEff,
+        INT bitRate,
+        INT averageBits,
+        INT *pAverageBitsPerFrame,
+        INT bitrateMode,
+        INT nSubFrames
+        )
 {
-  {  8000, 5 }, { 11025, 0 }, { 12000, 5 }, { 16000, 5 },
-  { 22050, 1 }, { 24000, 5 }, { 32000, 5 }, { 44100, 2 },
-  { 48000, 5 }, { 64000, 5 }, { 88200, 3 }, { 96000, 5 }
-};
+  INT transportBits, prevBitRate, averageBitsPerFrame, shift = 0, iter=0;
 
-/**
- * Get maximal scaling factor without losing samplingrate accuracy.
- *
- * \param  samplingRate Samplingrate to be used.
- * \return scaling value.
- */
-static int GetSrSf(const INT samplingRate)
-{
-  int i, result = 0;
+  while ( (frameLength & ~((1<<(shift+1))-1)) == frameLength
+    && (coreSamplingRate & ~((1<<(shift+1))-1)) == coreSamplingRate )
+  {
+    shift ++;
+  }
 
-  for (i=0; i<(int)(sizeof(samplingRateScalingTable)/sizeof(SR_SCALING_TAB)); i++) {
-    if ( samplingRateScalingTable[i].samplingRate == samplingRate ) {
-      result = samplingRateScalingTable[i].scalingFactor;
-      break;
+  do {
+    prevBitRate = bitRate;
+     averageBitsPerFrame = (bitRate*(frameLength>>shift)) / (coreSamplingRate>>shift) / nSubFrames;
+
+    if (pAverageBitsPerFrame != NULL) {
+      *pAverageBitsPerFrame = averageBitsPerFrame;
     }
-  }
-  return result;
+
+    if (hTpEnc != NULL) {
+      transportBits = transportEnc_GetStaticBits(hTpEnc, averageBitsPerFrame);
+    } else {
+      /* Assume some worst case */
+      transportBits = 208;
+    }
+
+    bitRate = FDKmax(bitRate, ((((40 * nChannels) + transportBits + frameLength) * (coreSamplingRate)) / frameLength) );
+    FDK_ASSERT(bitRate >= 0);
+
+    bitRate = FDKmin(bitRate, ((nChannelsEff * MIN_BUFSIZE_PER_EFF_CHAN)*(coreSamplingRate>>shift)) / (frameLength>>shift)) ;
+    FDK_ASSERT(bitRate >= 0);
+
+  } while (prevBitRate != bitRate && iter++ < 3) ;
+
+  return bitRate;
 }
 
-#define MIN_BUFSIZE_PER_EFF_CHAN 6144
 
 typedef struct
 {
@@ -349,16 +362,20 @@ AAC_ENCODER_ERROR FDKaacEnc_Initialize(HANDLE_AAC_ENC      hAacEnc,
 
   /* check bit rate */
 
-  /* check if bitRate is not too low or high */
-    averageBitsPerFrame = (config->bitRate*(config->framelength>>GetSrSf(config->sampleRate))) / (config->sampleRate>>GetSrSf(config->sampleRate)) / config->nSubFrames;
-
-  /* assume minimum static bits of 40 in each channel. */
-  if ( (averageBitsPerFrame <= ((40*config->nChannels) + transportEnc_GetStaticBits(hTpEnc, averageBitsPerFrame))) ||
-       ( ((config->bitRate*(config->framelength>>GetSrSf(config->sampleRate)))) >
-         ((FDKaacEnc_GetChannelModeConfiguration(config->channelMode)->nChannelsEff * MIN_BUFSIZE_PER_EFF_CHAN))*(config->sampleRate>>GetSrSf(config->sampleRate)) )
-     )
+  if (FDKaacEnc_LimitBitrate(
+          hTpEnc,
+          config->sampleRate,
+          config->framelength,
+          config->nChannels,
+          FDKaacEnc_GetChannelModeConfiguration(config->channelMode)->nChannelsEff,
+          config->bitRate,
+          config->averageBits,
+         &averageBitsPerFrame,
+          config->bitrateMode,
+          config->nSubFrames
+          ) != config->bitRate )
   {
-      return AAC_ENC_UNSUPPORTED_BITRATE;
+    return AAC_ENC_UNSUPPORTED_BITRATE;
   }
 
   if (config->syntaxFlags & AC_ER_VCB11) {
diff --git a/libAACenc/src/aacenc.h b/libAACenc/src/aacenc.h
index 66ef2b9..22228f6 100644
--- a/libAACenc/src/aacenc.h
+++ b/libAACenc/src/aacenc.h
@@ -159,6 +159,33 @@ typedef struct {
 
 typedef struct AAC_ENC *HANDLE_AAC_ENC;
 
+/**
+ * \brief Limit given bit rate to a valid value
+ * \param hTpEnc transport encoder handle
+ * \param coreSamplingRate the sample rate to be used for the AAC encoder
+ * \param frameLength the frameLength to be used for the AAC encoder
+ * \param nChannels number of total channels
+ * \param nChannelsEff number of effective channels
+ * \param bitRate the initial bit rate value for which the closest valid bit rate value is searched for
+ * \param averageBits average bits per frame for fixed framing. Set to -1 if not available.
+ * \param optional pointer where the current bits per frame are stored into.
+ * \param bitrateMode the current bit rate mode
+ * \param nSubFrames number of sub frames for super framing (not transport frames).
+ * \return a valid bit rate value as close as possible or identical to bitRate
+ */
+INT FDKaacEnc_LimitBitrate(
+        HANDLE_TRANSPORTENC hTpEnc,
+        INT coreSamplingRate,
+        INT frameLength,
+        INT nChannels,
+        INT nChannelsEff,
+        INT bitRate,
+        INT averageBits,
+        INT *pAverageBitsPerFrame,
+        INT bitrateMode,
+        INT nSubFrames
+        );
+
  /*-----------------------------------------------------------------------------
 
      functionname: FDKaacEnc_GetVBRBitrate
diff --git a/libAACenc/src/aacenc_lib.cpp b/libAACenc/src/aacenc_lib.cpp
index 65a9bfc..7984c13 100644
--- a/libAACenc/src/aacenc_lib.cpp
+++ b/libAACenc/src/aacenc_lib.cpp
@@ -388,6 +388,138 @@ AAC_ENCODER_ERROR aacEncDefaultConfig(HANDLE_AACENC_CONFIG hAacConfig,
     return AAC_ENC_OK;
 }
 
+static
+void aacEncDistributeSbrBits(CHANNEL_MAPPING *channelMapping, SBR_ELEMENT_INFO *sbrElInfo, INT bitRate)
+{
+  INT codebits = bitRate;
+  int el;
+
+  /* Copy Element info */
+  for (el=0; el<channelMapping->nElements; el++) {
+      sbrElInfo[el].ChannelIndex[0] = channelMapping->elInfo[el].ChannelIndex[0];
+      sbrElInfo[el].ChannelIndex[1] = channelMapping->elInfo[el].ChannelIndex[1];
+      sbrElInfo[el].elType          = channelMapping->elInfo[el].elType;
+      sbrElInfo[el].bitRate         = (INT)(fMultNorm(channelMapping->elInfo[el].relativeBits, (FIXP_DBL)bitRate));
+      sbrElInfo[el].instanceTag     = channelMapping->elInfo[el].instanceTag;
+      sbrElInfo[el].nChannelsInEl   = channelMapping->elInfo[el].nChannelsInEl;
+
+      codebits -= sbrElInfo[el].bitRate;
+  }
+  sbrElInfo[0].bitRate += codebits;
+}
+
+
+static
+INT aacEncoder_LimitBitrate(
+        const HANDLE_TRANSPORTENC hTpEnc,
+        const INT samplingRate,
+        const INT frameLength,
+        const INT nChannels,
+        const CHANNEL_MODE channelMode,
+        INT bitRate,
+        const INT nSubFrames,
+        const INT sbrActive,
+        const AUDIO_OBJECT_TYPE aot
+        )
+{
+  INT coreSamplingRate;
+  CHANNEL_MAPPING cm;
+
+  FDKaacEnc_InitChannelMapping(channelMode, CH_ORDER_MPEG, &cm);
+
+  if (sbrActive) {
+    /* Assume SBR rate ratio of 2:1 */
+    coreSamplingRate = samplingRate / 2;
+  } else {
+    coreSamplingRate = samplingRate;
+  }
+
+  /* Consider bandwidth channel bit rate limit (see bandwidth.cpp: GetBandwidthEntry()) */
+  if (aot == AOT_ER_AAC_LD || aot == AOT_ER_AAC_ELD) {
+    bitRate = FDKmin(360000*nChannels, bitRate);
+    bitRate = FDKmax(8000*nChannels, bitRate);
+  }
+
+  if (aot == AOT_AAC_LC || aot == AOT_SBR || aot == AOT_PS)  {
+    bitRate = FDKmin(576000*nChannels, bitRate);
+    /*bitRate = FDKmax(0*nChannels, bitRate);*/
+  }
+  
+
+  /* Limit bit rate in respect to the core coder */
+  bitRate = FDKaacEnc_LimitBitrate(
+          hTpEnc,
+          coreSamplingRate,
+          frameLength,
+          nChannels,
+          cm.nChannelsEff,
+          bitRate,
+          -1,
+          NULL,
+          -1,
+          nSubFrames
+          );
+
+  /* Limit bit rate in respect to available SBR modes if active */
+  if (sbrActive)
+  {
+    SBR_ELEMENT_INFO sbrElInfo[6];
+    INT sbrBitRate = 0;
+    int e, tooBig=-1;
+
+    FDK_ASSERT(cm.nElements <= (6));
+
+    /* Get bit rate for each SBR element */
+    aacEncDistributeSbrBits(&cm, sbrElInfo, bitRate);
+
+    for (e=0; e<cm.nElements; e++)
+    { 
+      INT sbrElementBitRateIn, sbrBitRateOut;
+
+      if (cm.elInfo[e].elType != ID_SCE && cm.elInfo[e].elType != ID_CPE) {
+        continue;
+      }
+      sbrElementBitRateIn = sbrElInfo[e].bitRate;
+      sbrBitRateOut = sbrEncoder_LimitBitRate(sbrElementBitRateIn , cm.elInfo[e].nChannelsInEl, coreSamplingRate, aot);
+      if (sbrBitRateOut == 0) {
+        return 0;
+      }
+      if (sbrElementBitRateIn < sbrBitRateOut) {
+        FDK_ASSERT(tooBig != 1);
+        tooBig = 0;
+        if (e == 0) {
+          sbrBitRate = 0;
+        }
+      }
+      if (sbrElementBitRateIn > sbrBitRateOut) {
+        FDK_ASSERT(tooBig != 0);
+        tooBig = 1;
+        if (e == 0) {
+          sbrBitRate = 5000000;
+        }
+      }
+      if (tooBig != -1)
+      {
+        INT sbrBitRateLimit = (INT)fDivNorm((FIXP_DBL)sbrBitRateOut, cm.elInfo[e].relativeBits);
+        if (tooBig) {
+          sbrBitRate = fMin(sbrBitRate, sbrBitRateLimit-16);
+          FDK_ASSERT( (INT)fMultNorm(cm.elInfo[e].relativeBits, (FIXP_DBL)sbrBitRate) < sbrBitRateOut);
+        } else {
+          sbrBitRate = fMax(sbrBitRate, sbrBitRateLimit+16);
+          FDK_ASSERT( (INT)fMultNorm(cm.elInfo[e].relativeBits, (FIXP_DBL)sbrBitRate) >= sbrBitRateOut);
+        }
+      }
+    }
+    if (tooBig != -1) {
+      bitRate = sbrBitRate;
+    }
+  }
+
+  FDK_ASSERT(bitRate > 0);
+
+  return bitRate;
+}
+
 /*
  * \brief Consistency check of given USER_PARAM struct and
  *   copy back configuration from public struct into internal
@@ -482,6 +614,19 @@ AACENC_ERROR FDKaacEnc_AdjustEncSettings(HANDLE_AACENCODER hAacEncoder,
           break;
     }
 
+    /* We need the frame length to call aacEncoder_LimitBitrate() */
+    hAacConfig->bitRate = aacEncoder_LimitBitrate(
+              NULL,
+              hAacConfig->sampleRate,
+              hAacConfig->framelength,
+              hAacConfig->nChannels,
+              hAacConfig->channelMode,
+              config->userBitrate,
+              hAacConfig->nSubFrames,
+              isSbrActive(hAacConfig),
+              hAacConfig->audioObjectType
+              );
+
     switch ( hAacConfig->audioObjectType ) {
       case AOT_ER_AAC_LD:
       case AOT_ER_AAC_ELD:
@@ -605,7 +750,6 @@ static AACENC_ERROR aacEncInit(HANDLE_AACENCODER  hAacEncoder,
 
     INT frameLength = hAacConfig->framelength;
 
-
     if ( (InitFlags & AACENC_INIT_CONFIG) )
     {
         CHANNEL_MODE prevChMode = hAacConfig->channelMode;
@@ -645,9 +789,7 @@ static AACENC_ERROR aacEncInit(HANDLE_AACENCODER  hAacEncoder,
         INT sbrError;
         SBR_ELEMENT_INFO sbrElInfo[(6)];
         CHANNEL_MAPPING channelMapping;
-        int el;
-        INT codebits  = hAacConfig->bitRate;
-        INT bitrateSc = CountLeadingBits(codebits);
+        
         AUDIO_OBJECT_TYPE aot = hAacConfig->audioObjectType;
 
         if ( FDKaacEnc_InitChannelMapping(hAacConfig->channelMode,
@@ -662,19 +804,7 @@ static AACENC_ERROR aacEncInit(HANDLE_AACENCODER  hAacEncoder,
             return AACENC_INIT_ERROR;
         }
 
-        /* Copy Element info */
-        for (el=0; el<channelMapping.nElements; el++) {
-            sbrElInfo[el].ChannelIndex[0] = channelMapping.elInfo[el].ChannelIndex[0];
-            sbrElInfo[el].ChannelIndex[1] = channelMapping.elInfo[el].ChannelIndex[1];
-            sbrElInfo[el].elType          = channelMapping.elInfo[el].elType;
-            sbrElInfo[el].bitRate         = (INT)(fMult(channelMapping.elInfo[el].relativeBits, (FIXP_DBL)(hAacConfig->bitRate<<bitrateSc))>>(bitrateSc));
-            sbrElInfo[el].instanceTag     = channelMapping.elInfo[el].instanceTag;
-            sbrElInfo[el].nChannelsInEl   = channelMapping.elInfo[el].nChannelsInEl;
-
-            sbrElInfo[el].bitRate         = fMult(channelMapping.elInfo[el].relativeBits, (FIXP_DBL)hAacConfig->bitRate);
-            codebits -= sbrElInfo[el].bitRate;
-        }
-        sbrElInfo[0].bitRate += codebits;
+        aacEncDistributeSbrBits(&channelMapping, sbrElInfo, hAacConfig->bitRate);
 
         UINT initFlag = 0;
         initFlag += (InitFlags & AACENC_INIT_STATES) ? 1 : 0;
diff --git a/libAACenc/src/psy_data.h b/libAACenc/src/psy_data.h
index af3cde8..38faac1 100644
--- a/libAACenc/src/psy_data.h
+++ b/libAACenc/src/psy_data.h
@@ -60,7 +60,7 @@ typedef shouldBeUnion{
 
 typedef struct{
   INT_PCM*                  psyInputBuffer;
-  FIXP_DBL  RESTRICT        overlapAddBuffer[1024];
+  FIXP_DBL                  overlapAddBuffer[1024];
 
   BLOCK_SWITCHING_CONTROL   blockSwitchingControl;              /* block switching */
   FIXP_DBL                  sfbThresholdnm1[MAX_SFB];           /* FDKaacEnc_PreEchoControl */
diff --git a/libAACenc/src/qc_main.cpp b/libAACenc/src/qc_main.cpp
index df9c4c4..3414310 100644
--- a/libAACenc/src/qc_main.cpp
+++ b/libAACenc/src/qc_main.cpp
@@ -1314,23 +1314,30 @@ AAC_ENCODER_ERROR FDKaacEnc_FinalizeBitConsumption(CHANNEL_MAPPING *cm,
     /* Now we can get the exact transport bit amount, and hopefully it is equal to the estimated value */
     exactTpBits = transportEnc_GetStaticBits(hTpEnc, qcOut->totalBits);
 
-    while (exactTpBits != qcKernel->globHdrBits && (max_iter-- > 0))
-    {
-      INT diffBits = qcKernel->globHdrBits-exactTpBits;
-      if (diffBits >= 0) {
-        /* move bits from header to payload */
-        qcOut->totFillBits     += diffBits;
-        qcOut->totalBits       += diffBits;
-        qcOut->grantedDynBits  += diffBits;
+    if (exactTpBits != qcKernel->globHdrBits) {
+      INT diffFillBits = 0;
+
+      /* Number of bits which can be moved to bitreservoir. */
+      INT bitsToBitres = qcKernel->globHdrBits - exactTpBits;
+
+      if (bitsToBitres>0) {
+        /* if bitreservoir can not take all bits, move ramaining bits to fillbits */
+        diffFillBits = FDKmax(0, bitsToBitres - (qcKernel->bitResTotMax-qcKernel->bitResTot));
       }
-      else {
-        /* get missing bits from bitreservoir */
-        qcKernel->bitResTot    += diffBits;
+      else if (bitsToBitres<0) {
+        /* if bits mus be taken from bitreservoir, reduce fillbits first. */
+        diffFillBits = (FDKmax(FDKmax(bitsToBitres, -qcKernel->bitResTot), -qcOut->totFillBits));
       }
-      qcKernel->globHdrBits = exactTpBits;
-      exactTpBits = transportEnc_GetStaticBits(hTpEnc, qcOut->totalBits);
+
+      diffFillBits = (diffFillBits+7)&~7; /* assure previous alignment */
+
+      qcOut->totFillBits     += diffFillBits;
+      qcOut->totalBits       += diffFillBits;
+      qcOut->grantedDynBits  += diffFillBits;
+
+      /* new header bits */
+      qcKernel->globHdrBits = transportEnc_GetStaticBits(hTpEnc, qcOut->totalBits);
     }
-    FDK_ASSERT(exactTpBits == qcKernel->globHdrBits);
   }
 
   /* Save total fill bits and distribut to alignment and fill bits */