media codec: add codec preferred format

This allows to support floating point encoding with opus.
Unused for now.

Change-Id: I5af298c8febdc24da6d30c7047301aae0038cdc0

src/media/media_codec.cpp

@@ -80,7 +80,8 @@ SystemAudioCodecInfo::SystemAudioCodecInfo(unsigned codecId,
                                            unsigned m_bitrate,
                                            unsigned m_sampleRate,
                                            unsigned m_nbChannels,
-                                           unsigned m_payloadType)
+                                           unsigned m_payloadType,
+                                           AVSampleFormat sampleFormat)
     : SystemCodecInfo(codecId,
                       m_avcodecId,
                       longName,
@@ -90,7 +91,7 @@ SystemAudioCodecInfo::SystemAudioCodecInfo(unsigned codecId,
                       m_type,
                       m_bitrate,
                       m_payloadType)
-    , audioformat {m_sampleRate, m_nbChannels}
+    , audioformat {m_sampleRate, m_nbChannels, sampleFormat}
 {}
 
 SystemAudioCodecInfo::~SystemAudioCodecInfo() {}

src/media/media_codec.h

@@ -132,7 +132,8 @@ struct SystemAudioCodecInfo : SystemCodecInfo
                          unsigned bitrate = 0,
                          unsigned sampleRate = 0,
                          unsigned nbChannels = 0,
-                         unsigned payloadType = 0);
+                         unsigned payloadType = 0,
+                         AVSampleFormat sampleFormat = AV_SAMPLE_FMT_S16);
 
     ~SystemAudioCodecInfo();
 

src/media/system_codec_container.cpp

@@ -121,7 +121,8 @@ SystemCodecContainer::initCodecConfig()
                                                0,
                                                48000,
                                                2,
-                                               104),
+                                               104,
+                                               AV_SAMPLE_FMT_FLT),
 
         std::make_shared<SystemAudioCodecInfo>(AV_CODEC_ID_ADPCM_G722,
                                                AV_CODEC_ID_ADPCM_G722,