int m4af_begin_write(m4af_ctx_t *ctx);
-int m4af_finalize(m4af_ctx_t *ctx);
+int m4af_finalize(m4af_ctx_t *ctx, int optimize);
void m4af_teardown(m4af_ctx_t **ctx);
int m4af_set_decoder_specific_info(m4af_ctx_t *ctx, uint32_t track_idx,
uint8_t *data, uint32_t size);
+void m4af_set_vbr_mode(m4af_ctx_t *ctx, uint32_t track_idx, int is_vbr);
+
void m4af_set_priming(m4af_ctx_t *ctx, uint32_t track_idx,
uint32_t encoder_delay, uint32_t padding);