avctx->frame_size = 1;
return -1;
static int adpcm_encode_init(AVCodecContext *avctx){    switch(avctx->codec->id) {    case CODEC_ID_ADPCM_IMA_QT:        avctx->frame_size = 64; /* XXX: ??? */        break;    case CODEC_ID_ADPCM_IMA_WAV:        avctx->frame_size = 64; /* XXX: ??? */        break;    default:        avctx->frame_size = 1;        break;    }    return 0;}