fec.cpp

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#include "rtp/fec.h"
 
#include <cassert>               // for assert
#include <cstdlib>               // for abort, free
#include <cstring>               // for strlen, strncmp, strtok_r, strdup
#include <exception>             // for exception
#include <ostream>               // for operator<<, basic_ostream, basic_ost...
#include <string>
 
#include "debug.h"
#include "rtp/ldgm.h"
#include "rtp/rs.h"
#include "rtp/rtp_callback.h"
#include "rtp/rtp_types.h"       // for PT_ENCRYPT_VIDEO, PT_ENCRYPT_VIDEO_LDGM
#include "ug_runtime_error.hpp"
#include "utils/macros.h"
 
using std::exception;
using std::stof;
using std::stoi;
using std::string;
 
fec *fec::create_from_config(const char *c_str, bool is_audio) noexcept
{
        try {
                if (strncmp(c_str, "LDGM percents ", strlen("LDGM percents ")) == 0) {
                        char *str = strdup(c_str);
                        char *ptr = str + strlen("LDGM percents ");
                        char *save_ptr = nullptr;
                        char *item = nullptr;
                        item = strtok_r(ptr, " ", &save_ptr);
                        assert (item != nullptr);
                        int mtu_len = stoi(item);
                        assert(mtu_len > 0);
                        item = strtok_r(nullptr, " ", &save_ptr);
                        assert (item != nullptr);
                        int data_len = stoi(item);
                        assert(data_len > 0);
                        item = strtok_r(nullptr, " ", &save_ptr);
                        assert (item != nullptr);
                        double loss_pct = stof(item);
                        assert(loss_pct > 0.0);
                        fec *ret = new ldgm(mtu_len, data_len, loss_pct);
                        free(str);
                        return ret;
                }
                if (strncmp(c_str, "LDGM cfg ", strlen("LDGM cfg ")) == 0) {
                        return new ldgm(c_str + strlen("LDGM cfg "));
                }
                if (strncmp(c_str, "RS cfg ", strlen("RS cfg ")) == 0) {
                        return new rs(c_str + strlen("rs cfg "), is_audio);
                }
                throw ug_runtime_error("Unrecognized FEC configuration!");
        } catch (string const &s) {
                LOG(LOG_LEVEL_ERROR) << s << "\n";
        } catch (exception const &e) {
                LOG(LOG_LEVEL_ERROR) << e.what() << "\n";
        } catch (int i) {
                if (i != 0) {
                        LOG(LOG_LEVEL_ERROR) << "FEC initialization returned " << i << "\n";
                }
        } catch (...) {
                LOG(LOG_LEVEL_ERROR) << "Unknown FEC error!\n";
        }
        return nullptr;
}
 
fec *fec::create_from_desc(struct fec_desc desc) noexcept
{
        try {
                switch (desc.type) {
                        case FEC_LDGM:
                                return new ldgm(desc.k, desc.m, desc.c, desc.seed);
                        case FEC_RS:
                                return new rs(desc.k, desc.k + desc.m);
                        default:
                                abort();
                }
        } catch (string const &s) {
                LOG(LOG_LEVEL_ERROR) << s << "\n";
        } catch (exception const &e) {
                LOG(LOG_LEVEL_ERROR) << e.what() << "\n";
        } catch (int i) {
                if (i != 0) {
                        LOG(LOG_LEVEL_ERROR) << "FEC initialization returned " << i << "\n";
                }
        } catch (...) {
                LOG(LOG_LEVEL_ERROR) << "Unknown FEC error!\n";
        }
        return nullptr;
 
}
 
int fec::pt_from_fec_type(enum tx_media_type media_type, enum fec_type fec_type, bool encrypted) throw()
{
        if (media_type == TX_MEDIA_VIDEO) {
                switch (fec_type) {
                case FEC_NONE:
                        return encrypted ? PT_ENCRYPT_VIDEO : PT_VIDEO;
                case FEC_LDGM:
                        return encrypted ? PT_ENCRYPT_VIDEO_LDGM : PT_VIDEO_LDGM;
                case FEC_RS:
                        return encrypted ? PT_ENCRYPT_VIDEO_RS : PT_VIDEO_RS;
                default: break;
                }
        } else {
                switch (fec_type) {
                case FEC_NONE:
                        return encrypted ? PT_ENCRYPT_AUDIO : PT_AUDIO;
                case FEC_RS:
                        return encrypted ? PT_ENCRYPT_AUDIO_RS : PT_AUDIO_RS;
                default: break;
                }
        }
        UG_ASSERT(0 && "Unsupported media/FEC type combination");
}
 
enum fec_type fec::fec_type_from_pt(int pt) throw()
{
        switch (pt) {
        case PT_VIDEO:
        case PT_ENCRYPT_VIDEO:
                return FEC_NONE;
        case PT_VIDEO_LDGM:
        case PT_ENCRYPT_VIDEO_LDGM:
                return FEC_LDGM;
        case PT_VIDEO_RS:
        case PT_ENCRYPT_VIDEO_RS:
                return FEC_RS;
        default:
                abort();
        }
}
 
 
int fec_pt_from_fec_type(enum tx_media_type media_type, enum fec_type fec_type, bool encrypted)
{
        return fec::pt_from_fec_type(media_type, fec_type, encrypted);
}