realloc when next size is larger than current

app/src/main/cpp/audio_player.cpp

@@ -286,6 +286,9 @@ AUDIO_PLAYER_FUNC(void, play, jstring input_jstr, jstring filter_jstr) {
     jmethodID fft_method = env->GetMethodID(player_class, "fftCallbackFromJNI", "([S)V");
 
     auto *fft_filter = static_cast<filter_sys_t *>(malloc(sizeof(filter_sys_t)));
+    fft_filter->nb_samples = 0;
+    fft_filter->data_size = 0;
+    fft_filter->data = nullptr;
     init_visualizer(fft_filter);
 
     //read audio frame
@@ -309,11 +312,8 @@ AUDIO_PLAYER_FUNC(void, play, jstring input_jstr, jstring filter_jstr) {
         }
         if (got_frame > 0) {
 
-            if (!fft_filter->data && frame->nb_samples > fft_filter->out_samples) {
-                fft_filter->nb_samples = frame->nb_samples;
-                fft_filter->data = static_cast<uint8_t *>(malloc(frame->nb_samples * sizeof(uint8_t)));
-            }
-            if (fft_filter->nb_samples == frame->nb_samples) {
+            ret = ensure_memory(fft_filter, frame->nb_samples);
+            if (ret == 0 && fft_filter->nb_samples == frame->nb_samples) {
                 memcpy(fft_filter->data, frame->data[0], static_cast<size_t>(frame->nb_samples));
                 fft_once(fft_filter);
                 fft_callback(env, thiz, fft_method, fft_filter->output, fft_filter->out_samples);

app/src/main/cpp/visualizer/execute_fft.c

@@ -224,6 +224,21 @@ void release_visualizer(filter_sys_t *p_filter)
     free(p_filter);
 }
 
+int ensure_memory(filter_sys_t *fft_filter, int nb_samples) {
+    if (nb_samples != fft_filter->nb_samples && nb_samples > fft_filter->out_samples) {
+        if (!fft_filter->data) {
+            fft_filter->data_size = nb_samples;
+            fft_filter->data = (uint8_t *) (malloc(nb_samples * sizeof(uint8_t)));
+        } else if (nb_samples > fft_filter->data_size) {
+            fft_filter->data_size = nb_samples;
+            fft_filter->data = (uint8_t *) (realloc(fft_filter->data, nb_samples * sizeof(uint8_t)));
+        }
+        if (!fft_filter->data) return -1;
+        fft_filter->nb_samples = nb_samples;
+    }
+    return 0;
+}
+
 void fft_once(filter_sys_t *p_sys)
 {
     int nb_samples = p_sys->nb_samples;

app/src/main/cpp/visualizer/execute_fft.h

@@ -30,6 +30,7 @@ typedef struct
     window_param wind_param;
 
     uint8_t *data;
+    int data_size;
     int nb_samples;
     int16_t * output;
     int out_samples;
@@ -49,4 +50,6 @@ int init_visualizer(filter_sys_t *p_sys);
 
 void release_visualizer(filter_sys_t *p_sys);
 
+int ensure_memory(filter_sys_t *fft_filter, int nb_samples);
+
 #endif //EXECUTE_FFT_H

app/src/main/java/com/frank/ffmpeg/activity/EqualizerActivity.kt

@@ -34,7 +34,7 @@ class EqualizerActivity : BaseActivity(), OnSeeBarListener {
 
     private val selectBandList = IntArray(bandsList.size)
     private val minEQLevel = 0
-    private val fftData = ByteArray(/*20*/256)
+    private val fftData = ByteArray(256)
     private var filterThread: Thread? = null
     private var mAudioPlayer: AudioPlayer? = null
     private var visualizerView: VisualizerView? = null
@@ -92,12 +92,10 @@ class EqualizerActivity : BaseActivity(), OnSeeBarListener {
         }
         mAudioPlayer = AudioPlayer()
         mAudioPlayer?.setOnFftCallback {
-            Log.e("Equalizer", "fft data[0]=" + it[0] + "--data[1]=" + it[1] + "--data[2]=" + it[2])
             if (visualizerView != null && it != null) {
                 for (i in it.indices) {
                     fftData[i] = (it[i]/*10/4.2f*/).toByte()
                 }
-                Log.e("Equalizer", "data[0]=" + fftData[0] + "--data[1]=" + fftData[1] + "--data[2]=" + fftData[2])
                 visualizerView!!.post { visualizerView!!.setWaveData(fftData) }
             }
         }