From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Thu, 21 Jul 2022 21:42:58 +0000 (+0200)
Subject: Remove the x264 VBV settings.
X-Git-Tag: 2.2.0~12
X-Git-Url: https://git.sesse.net/?p=nageru;a=commitdiff_plain;h=6df6a591ad1a7dbb9c8428e26cfe4953836c57e6

Remove the x264 VBV settings.

The user shouldn't generally muck around with this, so remove them.
---

diff --git a/nageru/flags.cpp b/nageru/flags.cpp
index 2a31422..3066d3a 100644
--- a/nageru/flags.cpp
+++ b/nageru/flags.cpp
@@ -176,10 +176,6 @@ void usage(Program program)
 	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");
-	fprintf(stderr, "                                  0 = no limit, default: same as --x264-bitrate, i.e., CBR)\n");
 	fprintf(stderr, "      --x264-param=NAME[,VALUE]   set any x264 parameter, for fine tuning\n");
 	if (program == PROGRAM_NAGERU) {
 		fprintf(stderr, "      --x264-separate-disk-preset x264 quality preset (default " X264_DEFAULT_PRESET ")\n");
@@ -293,8 +289,6 @@ void parse_flags(Program program, int argc, char * const argv[])
 		{ "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 },
 		{ "x264-separate-disk-preset", required_argument, 0, OPTION_X264_SEPARATE_DISK_PRESET },
 		{ "x264-separate-disk-tune", required_argument, 0, OPTION_X264_SEPARATE_DISK_TUNE },
@@ -485,12 +479,6 @@ void parse_flags(Program program, int argc, char * const argv[])
 		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;
-		case OPTION_X264_VBV_MAX_BITRATE:
-			global_flags.x264_vbv_max_bitrate = atoi(optarg);
-			break;
 		case OPTION_X264_PARAM:
 			global_flags.x264_extra_param.push_back(optarg);
 			break;
@@ -815,9 +803,6 @@ void parse_flags(Program program, int argc, char * const argv[])
 			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;
 	}
diff --git a/nageru/flags.h b/nageru/flags.h
index 40f88f3..54e971a 100644
--- a/nageru/flags.h
+++ b/nageru/flags.h
@@ -40,8 +40,6 @@ struct Flags {
 	bool x264_speedcontrol_verbose = false;
 	int x264_bitrate = -1;  // In kilobit/sec. -1 = not set = DEFAULT_X264_OUTPUT_BIT_RATE.
 	float x264_crf = HUGE_VAL;  // From 51 - QP_MAX_SPEC to 51. HUGE_VAL = not set = use x264_bitrate instead.
-	int x264_vbv_max_bitrate = -1;  // In kilobits. 0 = no limit, -1 = same as <x264_bitrate> (CBR).
-	int x264_vbv_buffer_size = -1;  // In kilobits. 0 = one-frame VBV, -1 = same as <x264_bitrate> (one-second VBV).
 	std::vector<std::string> x264_extra_param;  // In “key[,value]” format.
 
 	int av1_preset = DEFAULT_AV1_PRESET;
diff --git a/nageru/x264_encoder.cpp b/nageru/x264_encoder.cpp
index 6c46c98..b38711c 100644
--- a/nageru/x264_encoder.cpp
+++ b/nageru/x264_encoder.cpp
@@ -60,16 +60,8 @@ void update_vbv_settings(x264_param_t *param)
 	if (global_flags.x264_bitrate == -1) {
 		return;
 	}
-	if (global_flags.x264_vbv_buffer_size < 0) {
-		param->rc.i_vbv_buffer_size = param->rc.i_bitrate;  // One-second VBV.
-	} else {
-		param->rc.i_vbv_buffer_size = global_flags.x264_vbv_buffer_size;
-	}
-	if (global_flags.x264_vbv_max_bitrate < 0) {
-		param->rc.i_vbv_max_bitrate = param->rc.i_bitrate;  // CBR.
-	} else {
-		param->rc.i_vbv_max_bitrate = global_flags.x264_vbv_max_bitrate;
-	}
+	param->rc.i_vbv_buffer_size = param->rc.i_bitrate;  // One-second VBV.
+	param->rc.i_vbv_max_bitrate = param->rc.i_bitrate;  // CBR.
 }
 
 }  // namespace
@@ -212,16 +204,11 @@ void X264Encoder::init_x264()
 	} else {
 		param.rc.i_rc_method = X264_RC_ABR;
 		param.rc.i_bitrate = bitrate;
-	}
-	if (!use_separate_disk_params) {
-		update_vbv_settings(&param);
-	}
-	if (param.rc.i_vbv_max_bitrate > 0) {
-		// If the user wants VBV control to cap the max rate, it is
-		// also reasonable to assume that they are fine with the stream
-		// constantly being around that rate even for very low-complexity
-		// content; the obvious and extreme example being a static
-		// black picture.
+
+		// If the user wants to cap the max rate, it is also reasonable
+		// to assume that they are fine with the stream constantly
+		// being around that rate even for very low-complexity content;
+		// the obvious and extreme example being a static black picture.
 		//
 		// One would think it's fine to have low-complexity content use
 		// less bitrate, but it seems to cause problems in practice;
@@ -243,6 +230,9 @@ void X264Encoder::init_x264()
 		// thus ignores the parameter.)
 		param.rc.b_filler = 1;
 	}
+	if (!use_separate_disk_params) {
+		update_vbv_settings(&param);
+	}
 
 	// Occasionally players have problem with extremely low quantizers;
 	// be on the safe side. Shouldn't affect quality in any meaningful way.