vpxdec: support scaling output

Adds an option, --scale, that will rescale any frames produced by
the decoder that don't match the resolution of the first frame to
that resolution. This is useful for playback of files that use
spatial resampling.

Change-Id: I867adc650d535df7ec5b107549359712ea3aaaa0

1 files changed, 33 insertions, 1 deletions

diff --git a/vpxdec.c b/vpxdec.c
index f7281a4ef..30196ecc8 100644
--- a/vpxdec.c
+++ b/vpxdec.c
@@ -30,6 +30,7 @@
 #endif
 #include "tools_common.h"
 #include "nestegg/include/nestegg/nestegg.h"
+#include "third_party/libyuv/include/libyuv/scale.h"
 
 #if CONFIG_OS_SUPPORT
 #if defined(_MSC_VER)
@@ -93,6 +94,8 @@ static const arg_def_t verbosearg = ARG_DEF("v", "verbose", 0,
                                             "Show version string");
 static const arg_def_t error_concealment = ARG_DEF(NULL, "error-concealment", 0,
                                                    "Enable decoder error-concealment");
+static const arg_def_t scalearg = ARG_DEF("S", "scale", 0,
+                                            "Scale output frames uniformly");
 
 
 #if CONFIG_MD5
@@ -102,7 +105,7 @@ static const arg_def_t md5arg = ARG_DEF(NULL, "md5", 0,
 static const arg_def_t *all_args[] = {
   &codecarg, &use_yv12, &use_i420, &flipuvarg, &noblitarg,
   &progressarg, &limitarg, &skiparg, &postprocarg, &summaryarg, &outputfile,
-  &threadsarg, &verbosearg,
+  &threadsarg, &verbosearg, &scalearg,
 #if CONFIG_MD5
   &md5arg,
 #endif
@@ -708,6 +711,9 @@ int main(int argc, const char **argv_) {
   struct input_ctx        input = {0};
   int                     frames_corrupted = 0;
   int                     dec_flags = 0;
+  int                     do_scale;
+  int                     stream_w = 0, stream_h = 0;
+  vpx_image_t             *scaled_img = NULL;
 
   /* Parse command line */
   exec_name = argv_[0];
@@ -757,6 +763,8 @@ int main(int argc, const char **argv_) {
       cfg.threads = arg_parse_uint(&arg);
     else if (arg_match(&arg, &verbosearg, argi))
       quiet = 0;
+    else if (arg_match(&arg, &scalearg, argi))
+      do_scale = 1;
 
 #if CONFIG_VP8_DECODER
     else if (arg_match(&arg, &addnoise_level, argi)) {
@@ -1015,6 +1023,30 @@ int main(int argc, const char **argv_) {
       show_progress(frame_in, frame_out, dx_time);
 
     if (!noblit) {
+      if (do_scale) {
+        if (frame_out == 1) {
+          stream_w = img->d_w;
+          stream_h = img->d_h;
+          scaled_img = vpx_img_alloc(NULL, VPX_IMG_FMT_I420,
+                                     stream_w, stream_h, 16);
+        }
+        if (img && (img->d_w != stream_w || img->d_h != stream_h)) {
+          I420Scale(img->planes[VPX_PLANE_Y], img->stride[VPX_PLANE_Y],
+                    img->planes[VPX_PLANE_U], img->stride[VPX_PLANE_U],
+                    img->planes[VPX_PLANE_V], img->stride[VPX_PLANE_V],
+                    img->d_w, img->d_h,
+                    scaled_img->planes[VPX_PLANE_Y],
+                    scaled_img->stride[VPX_PLANE_Y],
+                    scaled_img->planes[VPX_PLANE_U],
+                    scaled_img->stride[VPX_PLANE_U],
+                    scaled_img->planes[VPX_PLANE_V],
+                    scaled_img->stride[VPX_PLANE_V],
+                    stream_w, stream_h,
+                    kFilterBox);
+          img = scaled_img;
+        }
+      }
+
       if (img) {
         unsigned int y;
         char out_fn[PATH_MAX];