Generalize FEC header formatting. (pt. 4)

webrtc/modules/rtp_rtcp/source/producer_fec.cc

Index: webrtc/modules/rtp_rtcp/source/producer_fec.cc
diff --git a/webrtc/modules/rtp_rtcp/source/producer_fec.cc b/webrtc/modules/rtp_rtcp/source/producer_fec.cc
index b928020df3211d33c7a9be5c838b39f49708faa9..277067ca1cf3666c928698342c4c72001a573bc5 100644
--- a/webrtc/modules/rtp_rtcp/source/producer_fec.cc
+++ b/webrtc/modules/rtp_rtcp/source/producer_fec.cc
@@ -24,12 +24,12 @@ namespace webrtc {
 constexpr size_t kRedForFecHeaderLength = 1;
 
 // This controls the maximum amount of excess overhead (actual - target)
-// allowed in order to trigger GenerateFec(), before |params_.max_fec_frames|
+// allowed in order to trigger EncodeFec(), before |params_.max_fec_frames|
 // is reached. Overhead here is defined as relative to number of media packets.
 constexpr int kMaxExcessOverhead = 50;  // Q8.
 
 // This is the minimum number of media packets required (above some protection
-// level) in order to trigger GenerateFec(), before |params_.max_fec_frames| is
+// level) in order to trigger EncodeFec(), before |params_.max_fec_frames| is
 // reached.
 constexpr size_t kMinMediaPackets = 4;
 
@@ -92,8 +92,8 @@ size_t RedPacket::length() const {
   return length_;
 }
 
-ProducerFec::ProducerFec(ForwardErrorCorrection* fec)
-    : fec_(fec),
+ProducerFec::ProducerFec()
+    : fec_(ForwardErrorCorrection::CreateUlpfec()),
       media_packets_(),
       generated_fec_packets_(),
       num_protected_frames_(0),
@@ -129,9 +129,8 @@ void ProducerFec::SetFecParameters(const FecProtectionParams* params,
   // protection in 'unequal protection mode') cannot exceed kMaxMediaPackets.
   RTC_DCHECK_GE(params->fec_rate, 0);
   RTC_DCHECK_LE(params->fec_rate, 255);
-  if (num_important_packets >
-      static_cast<int>(ForwardErrorCorrection::kMaxMediaPackets)) {
-    num_important_packets = ForwardErrorCorrection::kMaxMediaPackets;
+  if (num_important_packets > static_cast<int>(kUlpfecMaxMediaPackets)) {
+    num_important_packets = kUlpfecMaxMediaPackets;
   }
   // Store the new params and apply them for the next set of FEC packets being
   // produced.
@@ -153,8 +152,8 @@ int ProducerFec::AddRtpPacketAndGenerateFec(const uint8_t* data_buffer,
   }
   bool complete_frame = false;
   const bool marker_bit = (data_buffer[1] & kRtpMarkerBitMask) ? true : false;
-  if (media_packets_.size() < ForwardErrorCorrection::kMaxMediaPackets) {
-    // Generic FEC can only protect up to |kMaxMediaPackets| packets.
+  if (media_packets_.size() < kUlpfecMaxMediaPackets) {
+    // Generic FEC can only protect up to kMaxMediaPackets packets.
     std::unique_ptr<ForwardErrorCorrection::Packet> packet(
         new ForwardErrorCorrection::Packet());
     packet->length = payload_length + rtp_header_length;
@@ -173,16 +172,16 @@ int ProducerFec::AddRtpPacketAndGenerateFec(const uint8_t* data_buffer,
       (num_protected_frames_ == params_.max_fec_frames ||
        (ExcessOverheadBelowMax() && MinimumMediaPacketsReached()))) {
     RTC_DCHECK_LE(num_important_packets_,
-                  static_cast<int>(ForwardErrorCorrection::kMaxMediaPackets));
+                  static_cast<int>(kUlpfecMaxMediaPackets));
     // TODO(pbos): Consider whether unequal protection should be enabled or not,
     // it is currently always disabled.
     //
     // Since unequal protection is disabled, the value of
     // |num_important_packets_| has no importance when calling GenerateFec().
     constexpr bool kUseUnequalProtection = false;
-    int ret = fec_->GenerateFec(media_packets_, params_.fec_rate,
-                                num_important_packets_, kUseUnequalProtection,
-                                params_.fec_mask_type, &generated_fec_packets_);
+    int ret = fec_.EncodeFec(media_packets_, params_.fec_rate,
+                             num_important_packets_, kUseUnequalProtection,
+                             params_.fec_mask_type, &generated_fec_packets_);
     if (generated_fec_packets_.empty()) {
       num_protected_frames_ = 0;
       DeleteMediaPackets();
@@ -217,6 +216,10 @@ size_t ProducerFec::NumAvailableFecPackets() const {
   return generated_fec_packets_.size();
 }
 
+size_t ProducerFec::MaxPacketOverhead() const {
+  return fec_.MaxPacketOverhead();
+}
+
 std::vector<std::unique_ptr<RedPacket>> ProducerFec::GetFecPacketsAsRed(
     int red_payload_type,
     int ulpfec_payload_type,
@@ -239,15 +242,12 @@ std::vector<std::unique_ptr<RedPacket>> ProducerFec::GetFecPacketsAsRed(
     red_packet->SetSeqNum(seq_num++);
     red_packet->ClearMarkerBit();
     red_packet->AssignPayload(fec_packet->data, fec_packet->length);
-
     red_packets.push_back(std::move(red_packet));
   }
-
   // Reset state.
   DeleteMediaPackets();
   generated_fec_packets_.clear();
   num_protected_frames_ = 0;
-
   return red_packets;
 }
 
@@ -258,7 +258,7 @@ int ProducerFec::Overhead() const {
   // generation is implemented.
   RTC_DCHECK(!media_packets_.empty());
   int num_fec_packets =
-      fec_->GetNumberOfFecPackets(media_packets_.size(), params_.fec_rate);
+      fec_.NumFecPackets(media_packets_.size(), params_.fec_rate);
   // Return the overhead in Q8.
   return (num_fec_packets << 8) / media_packets_.size();
 }