[svc] 1. Add two pass RC options in vp9_spatial_scalable_encoder.

2. Add read/write for RC stats file
The two pass RC for svc does not work yet. This is just the first
step. We need further development to make it working.
Change-Id: I8ef0e177dff0b5ed3c97a916beea5123717cc6f2

examples/vp9_spatial_scalable_encoder.c

@@ -26,6 +26,7 @@
 #include "vpx/svc_context.h"
 #include "vpx/vp8cx.h"
 #include "vpx/vpx_encoder.h"
+#include "./vpxstats.h"
 
 static const struct arg_enum_list encoding_mode_enum[] = {
   {"i", INTER_LAYER_PREDICTION_I},
@@ -60,12 +61,19 @@ static const arg_def_t quantizers_arg =
 static const arg_def_t quantizers_keyframe_arg =
     ARG_DEF("qn", "quantizers-keyframe", 1, "quantizers for key frames (lowest "
         "to highest layer)");
+static const arg_def_t passes_arg =
+    ARG_DEF("p", "passes", 1, "Number of passes (1/2)");
+static const arg_def_t pass_arg =
+    ARG_DEF(NULL, "pass", 1, "Pass to execute (1/2)");
+static const arg_def_t fpf_name_arg =
+    ARG_DEF(NULL, "fpf", 1, "First pass statistics file name");
 
 static const arg_def_t *svc_args[] = {
   &encoding_mode_arg, &frames_arg,        &width_arg,       &height_arg,
   &timebase_arg,      &bitrate_arg,       &skip_frames_arg, &layers_arg,
   &kf_dist_arg,       &scale_factors_arg, &quantizers_arg,
-  &quantizers_keyframe_arg, NULL
+  &quantizers_keyframe_arg,               &passes_arg,       &pass_arg,
+  &fpf_name_arg,      NULL
 };
 
 static const SVC_ENCODING_MODE default_encoding_mode =
@@ -85,6 +93,10 @@ typedef struct {
   const char *output_filename;
   uint32_t frames_to_code;
   uint32_t frames_to_skip;
+  struct VpxInputContext input_ctx;
+  stats_io_t rc_stats;
+  int passes;
+  int pass;
 } AppInput;
 
 static const char *exec_name;
@@ -105,6 +117,9 @@ static void parse_command_line(int argc, const char **argv_,
   char **argi = NULL;
   char **argj = NULL;
   vpx_codec_err_t res;
+  int passes = 0;
+  int pass = 0;
+  const char *fpf_file_name = NULL;
 
   // initialize SvcContext with parameters that will be passed to vpx_svc_init
   svc_ctx->log_level = SVC_LOG_DEBUG;
@@ -159,11 +174,53 @@ static void parse_command_line(int argc, const char **argv_,
       vpx_svc_set_quantizers(svc_ctx, arg.val, 0);
     } else if (arg_match(&arg, &quantizers_keyframe_arg, argi)) {
       vpx_svc_set_quantizers(svc_ctx, arg.val, 1);
+    } else if (arg_match(&arg, &passes_arg, argi)) {
+      passes = arg_parse_uint(&arg);
+      if (passes < 1 || passes > 2) {
+        die("Error: Invalid number of passes (%d)\n", passes);
+      }
+    } else if (arg_match(&arg, &pass_arg, argi)) {
+      pass = arg_parse_uint(&arg);
+      if (pass < 1 || pass > 2) {
+        die("Error: Invalid pass selected (%d)\n", pass);
+      }
+    } else if (arg_match(&arg, &fpf_name_arg, argi)) {
+      fpf_file_name = arg.val;
     } else {
       ++argj;
     }
   }
 
+  if (passes == 0 || passes == 1) {
+    if (pass) {
+      fprintf(stderr, "pass is ignored since there's only one pass\n");
+    }
+    enc_cfg->g_pass = VPX_RC_ONE_PASS;
+  } else {
+    if (pass == 0) {
+      die("pass must be specified when passes is 2\n");
+    }
+
+    if (fpf_file_name == NULL) {
+      die("fpf must be specified when passes is 2\n");
+    }
+
+    if (pass == 1) {
+      enc_cfg->g_pass = VPX_RC_FIRST_PASS;
+      if (!stats_open_file(&app_input->rc_stats, fpf_file_name, 0)) {
+        fatal("Failed to open statistics store");
+      }
+    } else {
+      enc_cfg->g_pass = VPX_RC_LAST_PASS;
+      if (!stats_open_file(&app_input->rc_stats, fpf_file_name, 1)) {
+        fatal("Failed to open statistics store");
+      }
+      enc_cfg->rc_twopass_stats_in = stats_get(&app_input->rc_stats);
+    }
+    app_input->passes = passes;
+    app_input->pass = pass;
+  }
+
   // Check for unrecognized options
   for (argi = argv; *argi; ++argi)
     if (argi[0][0] == '-' && strlen(argi[0]) > 1)
@@ -234,10 +291,14 @@ int main(int argc, const char **argv) {
       VPX_CODEC_OK) {
     die("Failed to get output resolution");
   }
-  writer = vpx_video_writer_open(app_input.output_filename, kContainerIVF,
-                                 &info);
-  if (!writer)
-    die("Failed to open %s for writing\n", app_input.output_filename);
+
+  if (!(app_input.passes == 2 && app_input.pass == 1)) {
+    // We don't save the bitstream for the 1st pass on two pass rate control
+    writer = vpx_video_writer_open(app_input.output_filename, kContainerIVF,
+                                   &info);
+    if (!writer)
+      die("Failed to open %s for writing\n", app_input.output_filename);
+  }
 
   // skip initial frames
   for (i = 0; i < app_input.frames_to_skip; ++i)
@@ -254,11 +315,18 @@ int main(int argc, const char **argv) {
     if (res != VPX_CODEC_OK) {
       die_codec(&codec, "Failed to encode frame");
     }
-    if (vpx_svc_get_frame_size(&svc_ctx) > 0) {
-      vpx_video_writer_write_frame(writer,
-                                   vpx_svc_get_buffer(&svc_ctx),
-                                   vpx_svc_get_frame_size(&svc_ctx),
-                                   pts);
+    if (!(app_input.passes == 2 && app_input.pass == 1)) {
+      if (vpx_svc_get_frame_size(&svc_ctx) > 0) {
+        vpx_video_writer_write_frame(writer,
+                                     vpx_svc_get_buffer(&svc_ctx),
+                                     vpx_svc_get_frame_size(&svc_ctx),
+                                     pts);
+      }
+    }
+    if (vpx_svc_get_rc_stats_buffer_size(&svc_ctx) > 0) {
+      stats_write(&app_input.rc_stats,
+                  vpx_svc_get_rc_stats_buffer(&svc_ctx),
+                  vpx_svc_get_rc_stats_buffer_size(&svc_ctx));
     }
     ++frame_cnt;
     pts += frame_duration;
@@ -269,7 +337,12 @@ int main(int argc, const char **argv) {
   fclose(infile);
   if (vpx_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec");
 
-  vpx_video_writer_close(writer);
+  if (app_input.passes == 2)
+    stats_close(&app_input.rc_stats, 1);
+
+  if (writer) {
+    vpx_video_writer_close(writer);
+  }
 
   vpx_img_free(&raw);