diff -uNrp src/input/ffms.c src.new/input/ffms.c
--- src/input/ffms.c	2011-12-06 18:57:13 +0300
+++ src.new/input/ffms.c	2011-12-06 18:59:45 +0300
@@ -112,7 +112,7 @@ static int open_file( char *psz_filename
     int trackno = FFMS_GetFirstTrackOfType( idx, FFMS_TYPE_VIDEO, &e );
     FAIL_IF_ERROR( trackno < 0, "could not find video track\n" )
 
-    h->video_source = FFMS_CreateVideoSource( psz_filename, trackno, idx, 1, seekmode, &e );
+    h->video_source = FFMS_CreateVideoSource( psz_filename, trackno, idx, opt->demuxer_threads, seekmode, &e );
     FAIL_IF_ERROR( !h->video_source, "could not create video source\n" )
 
     h->track = FFMS_GetTrackFromVideo( h->video_source );
diff -uNrp src/input/input.h src.new/input/input.h
--- src/input/input.h	2011-12-06 18:57:13 +0300
+++ src.new/input/input.h	2011-12-06 19:00:00 +0300
@@ -44,6 +44,7 @@ typedef struct
     int output_csp; /* convert to this csp, if applicable */
     int output_range; /* user desired output range */
     int input_range; /* user override input range */
+    int demuxer_threads;
 } cli_input_opt_t;
 
 /* properties of the source given by the demuxer */
diff -uNrp src/input/lavf.c src.new/input/lavf.c
--- src/input/lavf.c	2011-12-06 18:57:13 +0300
+++ src.new/input/lavf.c	2011-12-06 19:00:20 +0300
@@ -184,6 +184,7 @@ static int open_file( char *psz_filename
     /* lavf is thread unsafe as calling av_read_frame invalidates previously read AVPackets */
     info->thread_safe  = 0;
     h->vfr_input       = info->vfr;
+    c->thread_count    = opt->demuxer_threads;
     FAIL_IF_ERROR( avcodec_open2( c, avcodec_find_decoder( c->codec_id ), NULL ),
                    "could not find decoder for video stream\n" )
 
diff -uNrp src/x264.c src.new/x264.c
--- src/x264.c	2011-12-06 18:58:20 +0300
+++ src.new/x264.c	2011-12-06 19:01:26 +0300
@@ -794,6 +794,7 @@ static void help( x264_param_t *defaults
     H1( "      --psnr                  Enable PSNR computation\n" );
     H1( "      --ssim                  Enable SSIM computation\n" );
     H1( "      --threads <integer>     Force a specific number of threads\n" );
+    H2( "      --demuxer-threads <integer> Force a specific number of threads for demuxer (lavf, ffms)\n" );
     H2( "      --sliced-threads        Low-latency but lower-efficiency threading\n" );
     H2( "      --thread-input          Run Avisynth in its own thread\n" );
     H2( "      --sync-lookahead <integer> Number of buffer frames for threaded lookahead\n" );
@@ -851,6 +852,7 @@ typedef enum
     OPT_TIMEBASE,
     OPT_PULLDOWN,
     OPT_LOG_LEVEL,
+    OPT_DEMUXER_THREADS,
     OPT_VIDEO_FILTER,
     OPT_INPUT_FMT,
     OPT_INPUT_RES,
@@ -962,6 +964,7 @@ static struct option long_options[] =
     { "zones",       required_argument, NULL, 0 },
     { "qpfile",      required_argument, NULL, OPT_QPFILE },
     { "threads",     required_argument, NULL, 0 },
+    { "demuxer-threads",   required_argument, NULL, OPT_DEMUXER_THREADS },
     { "sliced-threads",    no_argument, NULL, 0 },
     { "no-sliced-threads", no_argument, NULL, 0 },
     { "slice-max-size",    required_argument, NULL, 0 },
@@ -1329,6 +1332,9 @@ static int parse( int argc, char **argv,
             case OPT_THREAD_INPUT:
                 b_thread_input = 1;
                 break;
+            case OPT_DEMUXER_THREADS:
+                input_opt.demuxer_threads = atoi( optarg );
+                break;
             case OPT_QUIET:
                 cli_log_level = param->i_log_level = X264_LOG_NONE;
                 break;
@@ -1485,6 +1491,7 @@ generic_option:
     input_opt.seek = opt->i_seek;
     input_opt.progress = opt->b_progress;
     input_opt.output_csp = output_csp;
+    input_opt.demuxer_threads = x264_clip3( input_opt.demuxer_threads, 1, X264_THREAD_MAX );
 
     if( select_input( demuxer, demuxername, input_filename, &opt->hin, &info, &input_opt ) )
         return -1;