nellymoserdec: drop support for s16 output.

It internally decodes as float and then converts to s16 by a call to
float_to_int16(). The caller can do this just as well by using lavr.

libavcodec/nellymoserdec.c

@@ -48,13 +48,11 @@
 typedef struct NellyMoserDecodeContext {
     AVCodecContext* avctx;
     AVFrame         frame;
-    float          *float_buf;
     AVLFG           random_state;
     GetBitContext   gb;
     float           scale_bias;
     DSPContext      dsp;
     FFTContext      imdct_ctx;
-    FmtConvertContext fmt_conv;
     DECLARE_ALIGNED(32, float, imdct_buf)[2][NELLY_BUF_LEN];
     float          *imdct_out;
     float          *imdct_prev;
@@ -124,19 +122,8 @@ static av_cold int decode_init(AVCodecContext * avctx) {
 
     ff_dsputil_init(&s->dsp, avctx);
 
-    if (avctx->request_sample_fmt == AV_SAMPLE_FMT_FLT) {
-        s->scale_bias = 1.0/(32768*8);
-        avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
-    } else {
-        s->scale_bias = 1.0/(1*8);
-        avctx->sample_fmt = AV_SAMPLE_FMT_S16;
-        ff_fmt_convert_init(&s->fmt_conv, avctx);
-        s->float_buf = av_mallocz(NELLY_SAMPLES * sizeof(*s->float_buf));
-        if (!s->float_buf) {
-            av_log(avctx, AV_LOG_ERROR, "error allocating float buffer\n");
-            return AVERROR(ENOMEM);
-        }
-    }
+    s->scale_bias = 1.0/(32768*8);
+    avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
 
     /* Generate overlap window */
     if (!ff_sine_128[127])
@@ -157,7 +144,6 @@ static int decode_tag(AVCodecContext *avctx, void *data,
     int buf_size = avpkt->size;
     NellyMoserDecodeContext *s = avctx->priv_data;
     int blocks, i, ret;
-    int16_t *samples_s16;
     float   *samples_flt;
 
     blocks     = buf_size / NELLY_BLOCK_LEN;
@@ -183,18 +169,11 @@ static int decode_tag(AVCodecContext *avctx, void *data,
         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
         return ret;
     }
-    samples_s16 = (int16_t *)s->frame.data[0];
     samples_flt = (float   *)s->frame.data[0];
 
     for (i=0 ; i<blocks ; i++) {
-        if (avctx->sample_fmt == AV_SAMPLE_FMT_FLT) {
-            nelly_decode_block(s, buf, samples_flt);
-            samples_flt += NELLY_SAMPLES;
-        } else {
-            nelly_decode_block(s, buf, s->float_buf);
-            s->fmt_conv.float_to_int16(samples_s16, s->float_buf, NELLY_SAMPLES);
-            samples_s16 += NELLY_SAMPLES;
-        }
+        nelly_decode_block(s, buf, samples_flt);
+        samples_flt += NELLY_SAMPLES;
         buf += NELLY_BLOCK_LEN;
     }
 
@@ -207,7 +186,6 @@ static int decode_tag(AVCodecContext *avctx, void *data,
 static av_cold int decode_end(AVCodecContext * avctx) {
     NellyMoserDecodeContext *s = avctx->priv_data;
 
-    av_freep(&s->float_buf);
     ff_mdct_end(&s->imdct_ctx);
 
     return 0;
@@ -224,6 +202,5 @@ AVCodec ff_nellymoser_decoder = {
     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_PARAM_CHANGE,
     .long_name      = NULL_IF_CONFIG_SMALL("Nellymoser Asao"),
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
-                                                      AV_SAMPLE_FMT_S16,
                                                       AV_SAMPLE_FMT_NONE },
 };