avcodec/ralf: Move variable from context to stack

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavcodec/ralf.c

@@ -63,7 +63,6 @@ typedef struct RALFContext {
 
     unsigned bias[2];        ///< a constant value added to channel data after filtering
 
-    int num_blocks;          ///< number of blocks inside the frame
     int sample_offset;
     int block_size[1 << 12]; ///< size of the blocks
     int block_pts[1 << 12];  ///< block start time (in milliseconds)
@@ -418,7 +417,7 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
     int16_t *samples1;
     int ret;
     GetBitContext gb;
-    int table_size, table_bytes, i;
+    int table_size, table_bytes, num_blocks;
     const uint8_t *src, *block_pointer;
     int src_size;
     int bytes_left;
@@ -462,17 +461,17 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
         return AVERROR_INVALIDDATA;
     }
     init_get_bits(&gb, src + 2, table_size);
-    ctx->num_blocks = 0;
+    num_blocks = 0;
     while (get_bits_left(&gb) > 0) {
-        if (ctx->num_blocks >= FF_ARRAY_ELEMS(ctx->block_size))
+        if (num_blocks >= FF_ARRAY_ELEMS(ctx->block_size))
             return AVERROR_INVALIDDATA;
-        ctx->block_size[ctx->num_blocks] = get_bits(&gb, 13 + avctx->ch_layout.nb_channels);
+        ctx->block_size[num_blocks] = get_bits(&gb, 13 + avctx->ch_layout.nb_channels);
         if (get_bits1(&gb)) {
-            ctx->block_pts[ctx->num_blocks] = get_bits(&gb, 9);
+            ctx->block_pts[num_blocks] = get_bits(&gb, 9);
         } else {
-            ctx->block_pts[ctx->num_blocks] = 0;
+            ctx->block_pts[num_blocks] = 0;
         }
-        ctx->num_blocks++;
+        num_blocks++;
     }
 
     frame->nb_samples = ctx->max_frame_size;
@@ -483,7 +482,7 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
     block_pointer = src      + table_bytes + 2;
     bytes_left    = src_size - table_bytes - 2;
     ctx->sample_offset = 0;
-    for (i = 0; i < ctx->num_blocks; i++) {
+    for (int i = 0; i < num_blocks; i++) {
         if (bytes_left < ctx->block_size[i]) {
             av_log(avctx, AV_LOG_ERROR, "I'm pedaling backwards\n");
             break;