encoder: use avoption api

FFmpeg's AVOption API is more flexible and better suited than
AVDictionary for codec and format options.

This also allows to use strings in encoder.json, such as setting profile
to high (instead of 100).

Change-Id: I2039b2d039a87f8b3ed8ecb197dfa7b734c27950

src/media/media_encoder.cpp

@@ -107,7 +107,12 @@ MediaEncoder::setOptions(const MediaStream& opts)
 void
 MediaEncoder::setOptions(const MediaDescription& args)
 {
-    libav_utils::setDictValue(&options_, "payload_type", std::to_string(args.payload_type));
+    int ret;
+    if ((ret = av_opt_set_int(reinterpret_cast<void*>(outputCtx_),
+        "payload_type", args.payload_type, AV_OPT_SEARCH_CHILDREN)) < 0)
+        JAMI_ERR() << "Failed to set payload type: " << libav_utils::getError(ret);
+
+    // NOTE none of these are format options, and we don't have a codec context yet
     libav_utils::setDictValue(&options_, "max_rate", std::to_string(args.codec->bitrate));
     libav_utils::setDictValue(&options_, "crf", std::to_string(args.codec->quality));
 
@@ -203,7 +208,7 @@ MediaEncoder::initStream(const SystemCodecInfo& systemCodecInfo, AVBufferRef* fr
 
     currentStreamIdx_ = stream->index;
 
-    readConfig(&options_, encoderCtx);
+    readConfig(encoderCtx);
     if (avcodec_open2(encoderCtx, outputCodec_, &options_) < 0)
         throw MediaEncoderException("Could not open encoder");
 
@@ -846,7 +851,7 @@ MediaEncoder::stopEncoder()
 }
 
 void
-MediaEncoder::readConfig(AVDictionary** dict, AVCodecContext* encoderCtx)
+MediaEncoder::readConfig(AVCodecContext* encoderCtx)
 {
     std::string path = fileutils::get_config_dir() + DIR_SEPARATOR_STR + "encoder.json";
     std::string name = encoderCtx->codec->name;
@@ -868,7 +873,6 @@ MediaEncoder::readConfig(AVDictionary** dict, AVCodecContext* encoderCtx)
                 JAMI_ERR() << "Invalid encoder configuration: '" << name << "' is not an object";
                 return;
             }
-            // If users want to change these, they should use the settings page.
             for (Json::Value::const_iterator it = config.begin(); it != config.end(); ++it) {
                 Json::Value v = *it;
                 if (!it.key().isConvertibleTo(Json::ValueType::stringValue)
@@ -878,29 +882,12 @@ MediaEncoder::readConfig(AVDictionary** dict, AVCodecContext* encoderCtx)
                 }
                 const auto& key = it.key().asString();
                 const auto& value = v.asString();
-                // provides a way to override all AVCodecContext fields MediaEncoder sets
-                if (key == "parameters") // Used by MediaEncoder for profile-level-id, ignore
-                    continue;
-                else if (value.empty())
-                    libav_utils::setDictValue(dict, key, nullptr);
-                else if (key == "profile")
-                    encoderCtx->profile = v.asInt();
-                else if (key == "level")
-                    encoderCtx->level = v.asInt();
-                else if (key == "bit_rate")
-                    encoderCtx->bit_rate = v.asInt();
-                else if (key == "rc_buffer_size")
-                    encoderCtx->rc_buffer_size = v.asInt();
-                else if (key == "rc_min_rate")
-                    encoderCtx->rc_min_rate = v.asInt();
-                else if (key == "rc_max_rate")
-                    encoderCtx->rc_max_rate = v.asInt();
-                else if (key == "qmin")
-                    encoderCtx->qmin = v.asInt();
-                else if (key == "qmax")
-                    encoderCtx->qmax = v.asInt();
-                else
-                    libav_utils::setDictValue(dict, key, value);
+                int ret = av_opt_set(reinterpret_cast<void*>(encoderCtx),
+                                     key.c_str(), value.c_str(), AV_OPT_SEARCH_CHILDREN);
+                if (ret < 0) {
+                    JAMI_ERR() << "Failed to set option " << key << " in encoder context: "
+                        << libav_utils::getError(ret) << "\n";
+                }
             }
         } catch (const Json::Exception& e) {
             JAMI_ERR() << "Failed to load encoder configuration file: " << e.what();

src/media/media_encoder.h

@@ -152,7 +152,7 @@ private:
 #endif
 
 protected:
-    void readConfig(AVDictionary** dict, AVCodecContext* encoderCtx);
+    void readConfig(AVCodecContext* encoderCtx);
     AVDictionary* options_ = nullptr;
     MediaStream videoOpts_;
     MediaStream audioOpts_;