Adding third_party/openh264 build files for encoding (but not decoding).

Adds GYP and GN build files. Only building C++ code. Architecture-specific assembly code will be added in follow-up CL(s).

(This is a reupload of https://codereview.chromium.org/1403893007/ after having split it up into pieces and removed decoding and tests).

BUG=500605, 468365

Review URL: https://codereview.chromium.org/1446453004

Cr-Commit-Position: refs/heads/master@{#363443}

.gn

@@ -174,6 +174,7 @@ exec_script_whitelist = [
   "//third_party/harfbuzz-ng/BUILD.gn",
   "//third_party/libaddressinput/BUILD.gn",
   "//third_party/opus/BUILD.gn",
+  "//third_party/openh264/BUILD.gn",
   "//third_party/WebKit/Source/bindings/bindings.gni",
   "//third_party/WebKit/Source/bindings/scripts/scripts.gni",
   "//third_party/WebKit/Source/config.gni",

BUILD.gn

@@ -13,6 +13,7 @@ import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/ui.gni")
 import("//build_overrides/v8.gni")
 import("//media/media_options.gni")
+import("//third_party/openh264/openh264_args.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
@@ -587,6 +588,14 @@ group("both_gn_and_gyp") {
   if (is_ios || is_mac) {
     deps += [ "//media/cast:cast_h264_vt_encoder_unittests" ]
   }
+
+  if (use_openh264) {
+    deps += [
+      "//third_party/openh264:common",
+      "//third_party/openh264:encoder",
+      "//third_party/openh264:processing",
+    ]
+  }
 }
 
 group("gn_only") {

build/all.gyp

@@ -10,6 +10,9 @@
     # For Android-specific targets.
     'android_app_targets%': [],
   },
+  'includes': [
+    '../third_party/openh264/openh264_args.gypi',
+  ],
   'targets': [
     {
       'target_name': 'All',
@@ -286,6 +289,11 @@
             '../envoy/envoy.gyp:*',
           ],
         }],
+        ['use_openh264==1', {
+          'dependencies': [
+            '../third_party/openh264/openh264.gyp:*',
+          ],
+        }],
       ],
     }, # target_name: All
     {

build/gn_migration.gypi

@@ -528,8 +528,15 @@
         ['chromecast==1', {
           'dependencies': [
             '../chromecast/chromecast.gyp:cast_shell',
-          ]
-        }]
+          ],
+        }],
+        ['use_openh264==1', {
+          'dependencies': [
+            '../third_party/openh264/openh264.gyp:openh264_common',
+            '../third_party/openh264/openh264.gyp:openh264_processing',
+            '../third_party/openh264/openh264.gyp:openh264_encoder',
+          ],
+        }],
       ],
     },
     {

third_party/openh264/BUILD.gn

@@ -0,0 +1,75 @@
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//third_party/openh264/openh264_args.gni")
+
+assert(use_openh264)
+
+# Import source and include variables from openh264.gypi.
+openh264_gypi_values = exec_script("//build/gypi_to_gn.py",
+                                   [ rebase_path("openh264.gypi") ],
+                                   "scope")
+
+# Config shared by all openh264 targets.
+config("config") {
+  cflags = []
+  defines = []
+
+  # Compiler warnings to ignore.
+  if (!is_win) {
+    # GCC flags
+    cflags += [
+      "-Wno-header-hygiene",
+      "-Wno-unused-value",
+    ]
+  }
+
+  # Platform-specific defines.
+  if (is_android) {
+    # Android NDK is necessary for its cpufeatures and this define is what
+    # OpenH264 code uses to check if it should be used.
+    defines += [ "ANDROID_NDK" ]
+  }
+}
+
+source_set("common") {
+  sources = openh264_gypi_values.openh264_common_sources
+  include_dirs = openh264_gypi_values.openh264_common_includes
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+  configs += [ ":config" ]
+  deps = []
+  if (is_android) {
+    deps += [
+      # Defines "android_get/setCpu..." functions. The original OpenH264 build
+      # files replaces these using macros for "wels_..." versions of the same
+      # functions. We do not have access to these and use the <cpu-features.h>
+      # ones instead.
+      "//third_party/android_tools:cpu_features",
+    ]
+  }
+}
+
+source_set("processing") {
+  sources = openh264_gypi_values.openh264_processing_sources
+  include_dirs = openh264_gypi_values.openh264_processing_includes
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+  configs += [ ":config" ]
+  deps = [
+    ":common",
+  ]
+}
+
+source_set("encoder") {
+  sources = openh264_gypi_values.openh264_encoder_sources
+  include_dirs = openh264_gypi_values.openh264_encoder_includes
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+  configs += [ ":config" ]
+  deps = [
+    ":common",
+    ":processing",
+  ]
+}

third_party/openh264/DEPS

@@ -1,3 +0,0 @@
-include_rules = [
-  '+testing',
-]

third_party/openh264/openh264.gyp

@@ -0,0 +1,107 @@
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'includes': [
+    'openh264_args.gypi',
+  ],
+  'conditions': [
+    ['use_openh264==1', {
+      # Settings shared by all openh264 targets.
+      'target_defaults': {
+        'variables': {
+          'chromium_code': 0,
+          'conditions': [
+            ['OS!="win"', {
+              # GCC flags
+              'openh264_cflags_add': [
+                '-Wno-unused-value',
+              ],
+              'openh264_cflags_remove': [
+                '-Wheader-hygiene',
+              ],
+            },{
+              # Windows uses 'msvs_disabled_warnings' instead, for MSVC flags.
+              'openh264_cflags_add': [],
+              'openh264_cflags_remove': [],
+            }],
+          ],
+        },
+        'cflags': [ '<@(openh264_cflags_add)' ],
+        'cflags!': [ '<@(openh264_cflags_remove)' ],
+        'xcode_settings': {
+          'WARNING_CFLAGS': [ '<@(openh264_cflags_add)' ],
+          'WARNING_CFLAGS!': [ '<@(openh264_cflags_remove)' ],
+        },
+        'msvs_disabled_warnings': [
+          4324,  # structure was padded
+          4245,  # signed/unsigned mismatch
+          4701,  # uninitialized variable used
+          4702,  # unreachable code
+        ],
+
+        # Platform-specific defines.
+        'conditions': [
+          ['OS=="android"', {
+            'defines': [
+              # Android NDK is necessary for its cpufeatures and this define is
+              # what OpenH264 code uses to check if it should be used.
+              'ANDROID_NDK',
+            ],
+          }],
+        ],
+      },
+      'includes': [
+        'openh264.gypi',
+      ],
+      'targets': [
+        {
+          'target_name': 'openh264_common',
+          'type': 'static_library',
+          'conditions': [
+            ['OS=="android"', {
+              'dependencies': [
+                # Defines "android_get/setCpu..." functions. The original
+                # OpenH264 build files replaces these using macros for
+                # "wels_..." versions of the same functions. We do not have
+                # access to these and use the <cpu-features.h> ones instead.
+                '<(DEPTH)/build/android/ndk.gyp:cpu_features',
+              ],
+            }],
+          ],
+          'include_dirs+': [ '<@(openh264_common_includes)' ],
+          'sources': [ '<@(openh264_common_sources)' ],
+        },
+        {
+          'target_name': 'openh264_processing',
+          'type': 'static_library',
+          'dependencies': [
+            'openh264_common',
+          ],
+          'include_dirs+': [ '<@(openh264_processing_includes)' ],
+          'sources': [ '<@(openh264_processing_sources)' ],
+        },
+        {
+          'target_name': 'openh264_encoder',
+          'type': 'static_library',
+          'dependencies': [
+            'openh264_common',
+            'openh264_processing',
+          ],
+          'include_dirs+': [ '<@(openh264_encoder_includes)' ],
+          'sources': [ '<@(openh264_encoder_sources)' ],
+        },
+      ],
+    },{
+      # Building without OpenH264. Defining a dummy target because every build
+      # file needs to have at least one target.
+      'targets': [
+        {
+          'target_name': 'openh264_dummy_target',
+          'type': 'none',
+        }
+      ],
+    }],
+  ],
+}

third_party/openh264/openh264.gypi

@@ -0,0 +1,264 @@
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'variables': {
+    'openh264_common_includes': [
+      'src/codec/api/svc',
+      'src/codec/common/inc',
+      'src/codec/common/src',
+    ],
+    'openh264_common_sources': [
+      'src/codec/common/inc/WelsThreadLib.h',
+      'src/codec/common/inc/copy_mb.h',
+      'src/codec/common/inc/cpu.h',
+      'src/codec/common/inc/cpu_core.h',
+      'src/codec/common/inc/crt_util_safe_x.h',
+      'src/codec/common/inc/deblocking_common.h',
+      'src/codec/common/inc/expand_pic.h',
+      'src/codec/common/inc/golomb_common.h',
+      'src/codec/common/inc/intra_pred_common.h',
+      'src/codec/common/inc/ls_defines.h',
+      'src/codec/common/inc/macros.h',
+      'src/codec/common/inc/mc.h',
+      'src/codec/common/inc/measure_time.h',
+      'src/codec/common/inc/memory_align.h',
+      'src/codec/common/inc/sad_common.h',
+      'src/codec/common/inc/typedefs.h',
+      'src/codec/common/inc/utils.h',
+      'src/codec/common/inc/version.h',
+      'src/codec/common/inc/welsCodecTrace.h',
+      'src/codec/common/inc/wels_common_defs.h',
+      'src/codec/common/inc/wels_const_common.h',
+      'src/codec/common/src/WelsThreadLib.cpp',
+      'src/codec/common/src/common_tables.cpp',
+      'src/codec/common/src/copy_mb.cpp',
+      'src/codec/common/src/cpu.cpp',
+      'src/codec/common/src/crt_util_safe_x.cpp',
+      'src/codec/common/src/deblocking_common.cpp',
+      'src/codec/common/src/expand_pic.cpp',
+      'src/codec/common/src/intra_pred_common.cpp',
+      'src/codec/common/src/mc.cpp',
+      'src/codec/common/src/memory_align.cpp',
+      'src/codec/common/src/sad_common.cpp',
+      'src/codec/common/src/utils.cpp',
+      'src/codec/common/src/welsCodecTrace.cpp',
+    ],
+    # TODO(hbos): compile with *_asm_* sources
+    'openh264_common_sources_asm_x86': [
+      'src/codec/common/src/x86/cpuid.asm',
+      'src/codec/common/src/x86/deblock.asm',
+      'src/codec/common/src/x86/expand_picture.asm',
+      'src/codec/common/src/x86/intra_pred_com.asm',
+      'src/codec/common/src/x86/mb_copy.asm',
+      'src/codec/common/src/x86/mc_chroma.asm',
+      'src/codec/common/src/x86/mc_luma.asm',
+      'src/codec/common/src/x86/satd_sad.asm',
+      'src/codec/common/src/x86/vaa.asm',
+    ],
+    'openh264_common_sources_asm_arm': [
+      'src/codec/common/src/arm/copy_mb_neon.S',
+      'src/codec/common/src/arm/deblocking_neon.S',
+      'src/codec/common/src/arm/expand_picture_neon.S',
+      'src/codec/common/src/arm/intra_pred_common_neon.S',
+      'src/codec/common/src/arm/mc_neon.S',
+    ],
+    'openh264_common_sources_asm_arm64': [
+      'src/codec/common/src/arm64/copy_mb_aarch64_neon.S',
+      'src/codec/common/src/arm64/deblocking_aarch64_neon.S',
+      'src/codec/common/src/arm64/expand_picture_aarch64_neon.S',
+      'src/codec/common/src/arm64/intra_pred_common_aarch64_neon.S',
+      'src/codec/common/src/arm64/mc_aarch64_neon.S',
+    ],
+
+    'openh264_processing_includes': [
+      'src/codec/api/svc',
+      'src/codec/common/inc',
+      'src/codec/common/src',
+      'src/codec/processing/interface',
+      'src/codec/processing/interface/',
+      'src/codec/processing/src/adaptivequantization',
+      'src/codec/processing/src/backgrounddetection',
+      'src/codec/processing/src/common',
+      'src/codec/processing/src/complexityanalysis',
+      'src/codec/processing/src/denoise',
+      'src/codec/processing/src/downsample',
+      'src/codec/processing/src/imagerotate',
+      'src/codec/processing/src/scenechangedetection',
+      'src/codec/processing/src/scrolldetection',
+      'src/codec/processing/src/vaacalc',
+    ],
+    'openh264_processing_sources': [
+      'src/codec/processing/interface/IWelsVP.h',
+      'src/codec/processing/src/adaptivequantization/AdaptiveQuantization.cpp',
+      'src/codec/processing/src/adaptivequantization/AdaptiveQuantization.h',
+      'src/codec/processing/src/backgrounddetection/BackgroundDetection.cpp',
+      'src/codec/processing/src/backgrounddetection/BackgroundDetection.h',
+      'src/codec/processing/src/common/WelsFrameWork.cpp',
+      'src/codec/processing/src/common/WelsFrameWork.h',
+      'src/codec/processing/src/common/WelsFrameWorkEx.cpp',
+      'src/codec/processing/src/common/common.h',
+      'src/codec/processing/src/common/memory.cpp',
+      'src/codec/processing/src/common/memory.h',
+      'src/codec/processing/src/common/resource.h',
+      'src/codec/processing/src/common/typedef.h',
+      'src/codec/processing/src/common/util.h',
+      'src/codec/processing/src/complexityanalysis/ComplexityAnalysis.cpp',
+      'src/codec/processing/src/complexityanalysis/ComplexityAnalysis.h',
+      'src/codec/processing/src/denoise/denoise.cpp',
+      'src/codec/processing/src/denoise/denoise.h',
+      'src/codec/processing/src/denoise/denoise_filter.cpp',
+      'src/codec/processing/src/downsample/downsample.cpp',
+      'src/codec/processing/src/downsample/downsample.h',
+      'src/codec/processing/src/downsample/downsamplefuncs.cpp',
+      'src/codec/processing/src/imagerotate/imagerotate.cpp',
+      'src/codec/processing/src/imagerotate/imagerotate.h',
+      'src/codec/processing/src/imagerotate/imagerotatefuncs.cpp',
+      'src/codec/processing/src/scenechangedetection/SceneChangeDetection.cpp',
+      'src/codec/processing/src/scenechangedetection/SceneChangeDetection.h',
+      'src/codec/processing/src/scrolldetection/ScrollDetection.cpp',
+      'src/codec/processing/src/scrolldetection/ScrollDetection.h',
+      'src/codec/processing/src/scrolldetection/ScrollDetectionFuncs.cpp',
+      'src/codec/processing/src/scrolldetection/ScrollDetectionFuncs.h',
+      'src/codec/processing/src/vaacalc/vaacalcfuncs.cpp',
+      'src/codec/processing/src/vaacalc/vaacalculation.cpp',
+      'src/codec/processing/src/vaacalc/vaacalculation.h',
+    ],
+    # TODO(hbos): compile with *_asm_* sources
+    'openh264_processing_sources_asm_x86': [
+      'src/codec/processing/src/x86/denoisefilter.asm',
+      'src/codec/processing/src/x86/downsample_bilinear.asm',
+      'src/codec/processing/src/x86/vaa.asm',
+    ],
+    'openh264_processing_sources_asm_arm': [
+      'src/codec/processing/src/arm/adaptive_quantization.S',
+      'src/codec/processing/src/arm/down_sample_neon.S',
+      'src/codec/processing/src/arm/pixel_sad_neon.S',
+      'src/codec/processing/src/arm/vaa_calc_neon.S',
+    ],
+    'openh264_processing_sources_asm_arm64': [
+      'src/codec/processing/src/arm64/adaptive_quantization_aarch64_neon.S',
+      'src/codec/processing/src/arm64/down_sample_aarch64_neon.S',
+      'src/codec/processing/src/arm64/pixel_sad_aarch64_neon.S',
+      'src/codec/processing/src/arm64/vaa_calc_aarch64_neon.S',
+    ],
+
+    'openh264_encoder_includes': [
+      'src/codec/api/svc',
+      'src/codec/common/inc',
+      'src/codec/common/src',
+      'src/codec/encoder/core/inc',
+      'src/codec/encoder/core/src',
+      'src/codec/encoder/plus/inc',
+      'src/codec/encoder/plus/src',
+      'src/codec/processing/interface/',
+    ],
+    'openh264_encoder_sources': [
+      'src/codec/encoder/core/inc/as264_common.h',
+      'src/codec/encoder/core/inc/au_set.h',
+      'src/codec/encoder/core/inc/deblocking.h',
+      'src/codec/encoder/core/inc/decode_mb_aux.h',
+      'src/codec/encoder/core/inc/dq_map.h',
+      'src/codec/encoder/core/inc/encode_mb_aux.h',
+      'src/codec/encoder/core/inc/encoder.h',
+      'src/codec/encoder/core/inc/encoder_context.h',
+      'src/codec/encoder/core/inc/extern.h',
+      'src/codec/encoder/core/inc/get_intra_predictor.h',
+      'src/codec/encoder/core/inc/mb_cache.h',
+      'src/codec/encoder/core/inc/md.h',
+      'src/codec/encoder/core/inc/mt_defs.h',
+      'src/codec/encoder/core/inc/mv_pred.h',
+      'src/codec/encoder/core/inc/nal_encap.h',
+      'src/codec/encoder/core/inc/param_svc.h',
+      'src/codec/encoder/core/inc/parameter_sets.h',
+      'src/codec/encoder/core/inc/picture.h',
+      'src/codec/encoder/core/inc/picture_handle.h',
+      'src/codec/encoder/core/inc/property.h',
+      'src/codec/encoder/core/inc/rc.h',
+      'src/codec/encoder/core/inc/ref_list_mgr_svc.h',
+      'src/codec/encoder/core/inc/sample.h',
+      'src/codec/encoder/core/inc/set_mb_syn_cabac.h',
+      'src/codec/encoder/core/inc/set_mb_syn_cavlc.h',
+      'src/codec/encoder/core/inc/slice.h',
+      'src/codec/encoder/core/inc/slice_multi_threading.h',
+      'src/codec/encoder/core/inc/stat.h',
+      'src/codec/encoder/core/inc/svc_base_layer_md.h',
+      'src/codec/encoder/core/inc/svc_enc_frame.h',
+      'src/codec/encoder/core/inc/svc_enc_golomb.h',
+      'src/codec/encoder/core/inc/svc_enc_macroblock.h',
+      'src/codec/encoder/core/inc/svc_enc_slice_segment.h',
+      'src/codec/encoder/core/inc/svc_encode_mb.h',
+      'src/codec/encoder/core/inc/svc_encode_slice.h',
+      'src/codec/encoder/core/inc/svc_mode_decision.h',
+      'src/codec/encoder/core/inc/svc_motion_estimate.h',
+      'src/codec/encoder/core/inc/svc_set_mb_syn.h',
+      'src/codec/encoder/core/inc/svc_set_mb_syn_cavlc.h',
+      'src/codec/encoder/core/inc/vlc_encoder.h',
+      'src/codec/encoder/core/inc/wels_common_basis.h',
+      'src/codec/encoder/core/inc/wels_const.h',
+      'src/codec/encoder/core/inc/wels_func_ptr_def.h',
+      'src/codec/encoder/core/inc/wels_preprocess.h',
+      'src/codec/encoder/core/inc/wels_transpose_matrix.h',
+      'src/codec/encoder/core/src/au_set.cpp',
+      'src/codec/encoder/core/src/deblocking.cpp',
+      'src/codec/encoder/core/src/decode_mb_aux.cpp',
+      'src/codec/encoder/core/src/encode_mb_aux.cpp',
+      'src/codec/encoder/core/src/encoder.cpp',
+      'src/codec/encoder/core/src/encoder_data_tables.cpp',
+      'src/codec/encoder/core/src/encoder_ext.cpp',
+      'src/codec/encoder/core/src/get_intra_predictor.cpp',
+      'src/codec/encoder/core/src/md.cpp',
+      'src/codec/encoder/core/src/mv_pred.cpp',
+      'src/codec/encoder/core/src/nal_encap.cpp',
+      'src/codec/encoder/core/src/picture_handle.cpp',
+      'src/codec/encoder/core/src/property.cpp',
+      'src/codec/encoder/core/src/ratectl.cpp',
+      'src/codec/encoder/core/src/ref_list_mgr_svc.cpp',
+      'src/codec/encoder/core/src/sample.cpp',
+      'src/codec/encoder/core/src/set_mb_syn_cabac.cpp',
+      'src/codec/encoder/core/src/set_mb_syn_cavlc.cpp',
+      'src/codec/encoder/core/src/slice_multi_threading.cpp',
+      'src/codec/encoder/core/src/svc_base_layer_md.cpp',
+      'src/codec/encoder/core/src/svc_enc_slice_segment.cpp',
+      'src/codec/encoder/core/src/svc_encode_mb.cpp',
+      'src/codec/encoder/core/src/svc_encode_slice.cpp',
+      'src/codec/encoder/core/src/svc_mode_decision.cpp',
+      'src/codec/encoder/core/src/svc_motion_estimate.cpp',
+      'src/codec/encoder/core/src/svc_set_mb_syn_cabac.cpp',
+      'src/codec/encoder/core/src/svc_set_mb_syn_cavlc.cpp',
+      'src/codec/encoder/core/src/wels_preprocess.cpp',
+      'src/codec/encoder/plus/inc/welsEncoderExt.h',
+      'src/codec/encoder/plus/src/welsEncoderExt.cpp',
+      # Note: Purposefully excluded: 'src/codec/encoder/plus/src/DllEntry.cpp',
+      # This file is not built by the OpenH264 original build files.
+    ],
+    # TODO(hbos): compile with *_asm_* sources
+    'openh264_encoder_sources_asm_x86': [
+      'src/codec/encoder/core/x86/coeff.asm',
+      'src/codec/encoder/core/x86/dct.asm',
+      'src/codec/encoder/core/x86/intra_pred.asm',
+      'src/codec/encoder/core/x86/matrix_transpose.asm',
+      'src/codec/encoder/core/x86/memzero.asm',
+      'src/codec/encoder/core/x86/quant.asm',
+      'src/codec/encoder/core/x86/sample_sc.asm',
+      'src/codec/encoder/core/x86/score.asm',
+    ],
+    'openh264_encoder_sources_asm_arm': [
+      'src/codec/encoder/core/arm/intra_pred_neon.S',
+      'src/codec/encoder/core/arm/intra_pred_sad_3_opt_neon.S',
+      'src/codec/encoder/core/arm/memory_neon.S',
+      'src/codec/encoder/core/arm/pixel_neon.S',
+      'src/codec/encoder/core/arm/reconstruct_neon.S',
+      'src/codec/encoder/core/arm/svc_motion_estimation.S',
+    ],
+    'openh264_encoder_sources_asm_arm64': [
+      'src/codec/encoder/core/arm64/intra_pred_aarch64_neon.S',
+      'src/codec/encoder/core/arm64/intra_pred_sad_3_opt_aarch64_neon.S',
+      'src/codec/encoder/core/arm64/memory_aarch64_neon.S',
+      'src/codec/encoder/core/arm64/pixel_aarch64_neon.S',
+      'src/codec/encoder/core/arm64/reconstruct_aarch64_neon.S',
+      'src/codec/encoder/core/arm64/svc_motion_estimation_aarch64_neon.S',
+    ],
+  },
+}

third_party/openh264/openh264_args.gni

@@ -0,0 +1,12 @@
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//build/config/chrome_build.gni")
+
+declare_args() {
+  # Enable this to build OpenH264 (for encoding, not decoding).
+  # CHECK THE OPENH264 LICENSE/PATENT BEFORE BUILDING, see
+  # http://www.openh264.org/.
+  use_openh264 = false
+}

third_party/openh264/openh264_args.gypi

@@ -0,0 +1,12 @@
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'variables': {
+    # Enable this to build OpenH264 (for encoding, not decoding).
+    # CHECK THE OPENH264 LICENSE/PATENT BEFORE BUILDING, see
+    # http://www.openh264.org/.
+    'use_openh264%': 0,
+  },
+}