Support CRF for x264, similar to the CQP mode we already use in Quick Sync Video.

[nageru] / flags.cpp

diff --git a/flags.cpp b/flags.cpp
index ee575c57863984621386dcbcee11781857afa222..acd054181c2403de736d7b0fe1cbef8d734761be 100644 (file)
--- a/flags.cpp
+++ b/flags.cpp
@@ -25,6 +25,7 @@ enum LongOption {
        OPTION_X264_SPEEDCONTROL,
        OPTION_X264_SPEEDCONTROL_VERBOSE,
        OPTION_X264_BITRATE,
+       OPTION_X264_CRF,
        OPTION_X264_VBV_BUFSIZE,
        OPTION_X264_VBV_MAX_BITRATE,
        OPTION_X264_PARAM,
@@ -86,6 +87,7 @@ void usage()
        fprintf(stderr, "      --x264-speedcontrol-verbose  output speedcontrol debugging statistics\n");
        fprintf(stderr, "      --x264-bitrate              x264 bitrate (in kilobit/sec, default %d)\n",
                DEFAULT_X264_OUTPUT_BIT_RATE);
+       fprintf(stderr, "      --x264-crf=VALUE            quality-based VBR (-12 to 51), incompatible with --x264-bitrate and VBV\n");
        fprintf(stderr, "      --x264-vbv-bufsize          x264 VBV size (in kilobits, 0 = one-frame VBV,\n");
        fprintf(stderr, "                                  default: same as --x264-bitrate, that is, one-second VBV)\n");
        fprintf(stderr, "      --x264-vbv-max-bitrate      x264 local max bitrate (in kilobit/sec per --vbv-bufsize,\n");
@@ -157,6 +159,7 @@ void parse_flags(int argc, char * const argv[])
                { "x264-speedcontrol", no_argument, 0, OPTION_X264_SPEEDCONTROL },
                { "x264-speedcontrol-verbose", no_argument, 0, OPTION_X264_SPEEDCONTROL_VERBOSE },
                { "x264-bitrate", required_argument, 0, OPTION_X264_BITRATE },
+               { "x264-crf", required_argument, 0, OPTION_X264_CRF },
                { "x264-vbv-bufsize", required_argument, 0, OPTION_X264_VBV_BUFSIZE },
                { "x264-vbv-max-bitrate", required_argument, 0, OPTION_X264_VBV_MAX_BITRATE },
                { "x264-param", required_argument, 0, OPTION_X264_PARAM },
@@ -288,6 +291,9 @@ void parse_flags(int argc, char * const argv[])
                case OPTION_X264_BITRATE:
                        global_flags.x264_bitrate = atoi(optarg);
                        break;
+               case OPTION_X264_CRF:
+                       global_flags.x264_crf = atof(optarg);
+                       break;
                case OPTION_X264_VBV_BUFSIZE:
                        global_flags.x264_vbv_buffer_size = atoi(optarg);
                        break;
@@ -481,4 +487,16 @@ void parse_flags(int argc, char * const argv[])
        if (global_flags.max_input_queue_frames > 10) {
                fprintf(stderr, "WARNING: --max-input-queue-frames has little effect over 10.\n");
        }
+
+       if (!isinf(global_flags.x264_crf)) {  // CRF mode is selected.
+               if (global_flags.x264_bitrate != -1) {
+                       fprintf(stderr, "ERROR: --x264-bitrate and --x264-crf are mutually incompatible.\n");
+                       exit(1);
+               }
+               if (global_flags.x264_vbv_max_bitrate != -1 && global_flags.x264_vbv_buffer_size != -1) {
+                       fprintf(stderr, "WARNING: VBV settings are ignored with --x264-crf.\n");
+               }
+       } else if (global_flags.x264_bitrate == -1) {
+               global_flags.x264_bitrate = DEFAULT_X264_OUTPUT_BIT_RATE;
+       }
 }