mediacodec: Don't return frames before the output format is set

The decoder on Sony Xperia Z1 seems to return one frame before
the output format is set (and calling getOutputFormat() at this
point throws an IllegalStateException). Therefore just drop any
frames that are returned before the output format has been set.
Signed-off-by: Martin Storsjö <martin@martin.st>

modules/codec/omxil/android_mediacodec.c

@@ -398,6 +398,11 @@ static void GetOutput(decoder_t *p_dec, JNIEnv *env, picture_t **pp_pic, int loo
         int index = (*env)->CallIntMethod(env, p_sys->codec, p_sys->dequeue_output_buffer,
                                           p_sys->buffer_info, (jlong) 0);
         if (index >= 0) {
+            if (!p_sys->pixel_format) {
+                msg_Warn(p_dec, "Buffers returned before output format is set, dropping frame");
+                (*env)->CallVoidMethod(env, p_sys->codec, p_sys->release_output_buffer, index, false);
+                continue;
+            }
             jobject buf = (*env)->GetObjectArrayElement(env, p_sys->output_buffers, index);
             jsize buf_size = (*env)->GetDirectBufferCapacity(env, buf);
             uint8_t *ptr = (*env)->GetDirectBufferAddress(env, buf);