+static int latm_context2profilelevel(AVCodecContext *c)
+{
+ /* MP4A-LATM
+ * The RTP payload format specification is described in RFC 3016
+ * The encoding specifications are provided in ISO/IEC 14496-3 */
+
+ int profile_level = 0x2B;
+
+ /* TODO: AAC Profile only supports AAC LC Object Type.
+ * Different Object Types should implement different Profile Levels */
+
+ if (c->sample_rate <= 24000) {
+ if (c->channels <= 2)
+ profile_level = 0x28; // AAC Profile, Level 1
+ } else if (c->sample_rate <= 48000) {
+ if (c->channels <= 2) {
+ profile_level = 0x29; // AAC Profile, Level 2
+ } else if (c->channels <= 5) {
+ profile_level = 0x2A; // AAC Profile, Level 4
+ }
+ } else if (c->sample_rate <= 96000) {
+ if (c->channels <= 5) {
+ profile_level = 0x2B; // AAC Profile, Level 5
+ }
+ }
+
+ return profile_level;
+}
+
+static char *latm_context2config(AVCodecContext *c)
+{
+ /* MP4A-LATM
+ * The RTP payload format specification is described in RFC 3016
+ * The encoding specifications are provided in ISO/IEC 14496-3 */
+
+ uint8_t config_byte[6];
+ int rate_index;
+ char *config;
+
+ for (rate_index = 0; rate_index < 16; rate_index++)
+ if (avpriv_mpeg4audio_sample_rates[rate_index] == c->sample_rate)
+ break;
+ if (rate_index == 16) {
+ av_log(c, AV_LOG_ERROR, "Unsupported sample rate\n");
+ return NULL;
+ }
+
+ config_byte[0] = 0x40;
+ config_byte[1] = 0;
+ config_byte[2] = 0x20 | rate_index;
+ config_byte[3] = c->channels << 4;
+ config_byte[4] = 0x3f;
+ config_byte[5] = 0xc0;
+
+ config = av_malloc(6*2+1);
+ if (!config) {
+ av_log(c, AV_LOG_ERROR, "Cannot allocate memory for the config info.\n");
+ return NULL;
+ }
+ ff_data_to_hex(config, config_byte, 6, 1);
+ config[12] = 0;
+
+ return config;
+}
+
+static char *sdp_write_media_attributes(char *buff, int size, AVCodecContext *c, int payload_type, AVFormatContext *fmt)