Index: encoder/slicetype.c
===================================================================
--- encoder/slicetype.c	(r‚vision 656)
+++ encoder/slicetype.c	(copie de travail)
@@ -459,6 +459,14 @@
     {
         frm = h->frames.next[bframes];
 
+        /* Force intra frame when requested */
+        if( h->i_intras && frm->i_frame == h->intras[h->i_current_intra])
+        {
+            frm->i_type = X264_TYPE_IDR;
+            if (h->i_current_intra < h->i_intras-1)
+                h->i_current_intra++;
+        }
+
         /* Limit GOP size */
         if( frm->i_frame - h->frames.i_last_idr >= h->param.i_keyint_max )
         {
Index: encoder/encoder.c
===================================================================
--- encoder/encoder.c	(r‚vision 656)
+++ encoder/encoder.c	(copie de travail)
@@ -101,7 +101,45 @@
 }
 #endif
 
+/* */
+static int x264_parse_intras( x264_t *h )
+{
+    x264_param_t *param = &h->param;
 
+    if( param->psz_intras && !param->i_intras )
+    {
+        char *p;
+        int  i;
+
+        param->i_intras = 1;
+        for( p = param->psz_intras; *p; p++ )
+            param->i_intras += (*p == ',');
+        param->intras = x264_malloc( param->i_intras * sizeof(unsigned int) );
+        p = param->psz_intras;
+        for( i = 0; i < param->i_intras; i++)
+        {
+            if ( 1 != sscanf(p, "%u", param->intras+i) )
+            {
+                char *slash = strchr(p, ',');
+                if(slash) *slash = '\0';
+                x264_log( h, X264_LOG_ERROR, "invalid index: \"%s\"\n", p );
+                return -1;
+            }
+            else
+              {
+                printf("Will force %u as intra\n", param->intras[i]);
+              }
+            p = strchr(p, ',') + 1;
+        }
+    }
+
+    h->i_intras = param->i_intras;
+    h->intras = x264_malloc( param->i_intras * sizeof(unsigned int) );
+    memcpy( h->intras, param->intras, param->i_intras * sizeof(unsigned int) );
+
+    return 0;
+}
+
 /* Fill "default" values */
 static void x264_slice_header_init( x264_t *h, x264_slice_header_t *sh,
                                     x264_sps_t *sps, x264_pps_t *pps,
@@ -722,6 +760,12 @@
     }
 #endif
 
+    if( x264_parse_intras( h ) < 0 )
+    {
+        x264_free( h );
+        return NULL;
+    }
+
     return h;
 }
 
Index: x264.c
===================================================================
--- x264.c	(r‚vision 656)
+++ x264.c	(copie de travail)
@@ -213,6 +213,7 @@
         "                                  where <option> is either\n"
         "                                      q=<integer> (force QP)\n"
         "                                  or  b=<float> (bitrate multiplier)\n" );
+    H1( "      --intras <frame0>,<frame1>,... Indices of frames to encode as intra\n");
     H1( "      --qpfile <string>       Force frametypes and QPs\n" );
     H0( "\n" );
     H0( "Analysis:\n" );
@@ -433,6 +434,7 @@
             { "qblur",   required_argument, NULL, 0 },
             { "cplxblur",required_argument, NULL, 0 },
             { "zones",   required_argument, NULL, 0 },
+            { "intras",  required_argument, NULL, 0 },
             { "qpfile",  required_argument, NULL, OPT_QPFILE },
             { "threads", required_argument, NULL, 0 },
             { "thread-input", no_argument,  NULL, OPT_THREAD_INPUT },