Use signed int type for av1_lookahead_init params

Callers of av1_lookahead_init pass signed int variables as those
parameters, and av1_lookahead_init passes those parameters to a function
that receives signed int parameters.

Also change av1_lookahead_depth to return signed int.

Change-Id: Ia58970004473534c8090e0bf5ba74d47dc4584c9

av1/encoder/lookahead.c

diff --git a/av1/encoder/lookahead.c b/av1/encoder/lookahead.c
index 1011799..162a245 100644
--- a/av1/encoder/lookahead.c
+++ b/av1/encoder/lookahead.c
@@ -42,11 +42,13 @@
   }
 }
 
-struct lookahead_ctx *av1_lookahead_init(
-    unsigned int width, unsigned int height, unsigned int subsampling_x,
-    unsigned int subsampling_y, int use_highbitdepth, unsigned int depth,
-    const int border_in_pixels, int byte_alignment, int num_lap_buffers,
-    bool is_all_intra, bool alloc_pyramid) {
+struct lookahead_ctx *av1_lookahead_init(int width, int height,
+                                         int subsampling_x, int subsampling_y,
+                                         int use_highbitdepth, int depth,
+                                         const int border_in_pixels,
+                                         int byte_alignment,
+                                         int num_lap_buffers, bool is_all_intra,
+                                         bool alloc_pyramid) {
   int lag_in_frames = AOMMAX(1, depth);
 
   // For all-intra frame encoding, previous source frames are not required.
@@ -66,7 +68,6 @@
   // Allocate the lookahead structures
   struct lookahead_ctx *ctx = calloc(1, sizeof(*ctx));
   if (ctx) {
-    unsigned int i;
     ctx->max_sz = depth;
     ctx->push_frame_count = 0;
     ctx->max_pre_frames = max_pre_frames;
@@ -78,7 +79,7 @@
     }
     ctx->buf = calloc(depth, sizeof(*ctx->buf));
     if (!ctx->buf) goto fail;
-    for (i = 0; i < depth; i++) {
+    for (int i = 0; i < depth; i++) {
       if (aom_realloc_frame_buffer(
               &ctx->buf[i].img, width, height, subsampling_x, subsampling_y,
               use_highbitdepth, border_in_pixels, byte_alignment, NULL, NULL,
@@ -207,8 +208,7 @@
   return buf;
 }
 
-unsigned int av1_lookahead_depth(struct lookahead_ctx *ctx,
-                                 COMPRESSOR_STAGE stage) {
+int av1_lookahead_depth(struct lookahead_ctx *ctx, COMPRESSOR_STAGE stage) {
   assert(ctx != NULL);
 
   struct read_ctx *read_ctx = &ctx->read_ctxs[stage];

av1/encoder/lookahead.h

diff --git a/av1/encoder/lookahead.h b/av1/encoder/lookahead.h
index 0a33120..2d2456a 100644
--- a/av1/encoder/lookahead.h
+++ b/av1/encoder/lookahead.h
@@ -66,11 +66,13 @@
  * The lookahead stage is a queue of frame buffers on which some analysis
  * may be done when buffers are enqueued.
  */
-struct lookahead_ctx *av1_lookahead_init(
-    unsigned int width, unsigned int height, unsigned int subsampling_x,
-    unsigned int subsampling_y, int use_highbitdepth, unsigned int depth,
-    const int border_in_pixels, int byte_alignment, int num_lap_buffers,
-    bool is_all_intra, bool alloc_pyramid);
+struct lookahead_ctx *av1_lookahead_init(int width, int height,
+                                         int subsampling_x, int subsampling_y,
+                                         int use_highbitdepth, int depth,
+                                         const int border_in_pixels,
+                                         int byte_alignment,
+                                         int num_lap_buffers, bool is_all_intra,
+                                         bool alloc_pyramid);
 
 /**\brief Destroys the lookahead stage
  */
@@ -124,8 +126,7 @@
 
 /**\brief Get the number of frames currently in the lookahead queue
  */
-unsigned int av1_lookahead_depth(struct lookahead_ctx *ctx,
-                                 COMPRESSOR_STAGE stage);
+int av1_lookahead_depth(struct lookahead_ctx *ctx, COMPRESSOR_STAGE stage);
 
 /**\brief Get pop_sz value
  */

av1/encoder/pass2_strategy.c

diff --git a/av1/encoder/pass2_strategy.c b/av1/encoder/pass2_strategy.c
index b43532a..244b906 100644
--- a/av1/encoder/pass2_strategy.c
+++ b/av1/encoder/pass2_strategy.c
@@ -2147,7 +2147,7 @@
 
 static void correct_frames_to_key(AV1_COMP *cpi) {
   int lookahead_size =
-      (int)av1_lookahead_depth(cpi->ppi->lookahead, cpi->compressor_stage);
+      av1_lookahead_depth(cpi->ppi->lookahead, cpi->compressor_stage);
   if (lookahead_size <
       av1_lookahead_pop_sz(cpi->ppi->lookahead, cpi->compressor_stage)) {
     assert(