Disable writing VPS when vps_period is negative.

Turns vps_period in struct encoder_control_t into a signed value.
Negative values are interpreted as "never send parameter sets."

src/encoder.c

@@ -433,7 +433,11 @@ encoder_control_t* kvz_encoder_control_init(const kvz_config *const cfg) {
   // AUD
   encoder->aud_enable = (int8_t)encoder->cfg->aud_enable;
 
-  encoder->vps_period = encoder->cfg->vps_period * encoder->cfg->intra_period;
+  if (encoder->cfg->vps_period >= 0) {
+    encoder->vps_period = encoder->cfg->vps_period * encoder->cfg->intra_period;
+  } else {
+    encoder->vps_period = -1;
+  }
 
   return encoder;
 

src/encoder.h

@@ -140,7 +140,7 @@ typedef struct encoder_control_t
   } pu_depth_inter, pu_depth_intra;
   
   // How often Video Parameter Set is re-sent.
-  uint32_t vps_period;
+  int32_t vps_period;
 
   bool sign_hiding;
 

src/encoder_state-bitstream.c

@@ -838,7 +838,7 @@ static void encoder_state_write_bitstream_main(encoder_state_t * const state)
   }
   
   if ((encoder->vps_period > 0 && state->global->frame % encoder->vps_period == 0)
-      || state->global->frame == 0)
+      || (state->global->frame == 0 && encoder->vps_period >= 0))
   {
     first_nal_in_au = false;
     kvz_encoder_state_write_parameter_sets(&state->stream, state);

src/kvazaar.h

@@ -106,7 +106,18 @@ typedef struct kvz_config
 {
   int32_t qp;        /*!< \brief Quantization parameter */
   int32_t intra_period; /*!< \brief the period of intra frames in stream */
-  int32_t vps_period; /*!< \brief how often the vps is re-sent */
+
+  /** \brief How often the VPS, SPS and PPS are re-sent
+   *
+   * -1: never
+   *  0: first frame only
+   *  1: every intra frame
+   *  2: every other intra frame
+   *  3: every third intra frame
+   *  and so on
+   */
+  int32_t vps_period;
+
   int32_t width;   /*!< \brief frame width, must be a multiple of 8 */
   int32_t height;  /*!< \brief frame height, must be a multiple of 8 */
   double framerate; /*!< \brief Input framerate */