Webm-tools 设置问题

Question

我已经尝试设置了半天了，我越来越绝望，请帮助。 我正在关注https://developer.mozilla.org/en-US/docs/Web/HTML/DASH_Adaptive_Streaming_for_HTML_5_Video，但我被困在第 3 步，因为我无法设置 dash_manifest（来自 webm-tools）。运行 cmake path/to/webmtools 时出现的错误是：

CMake Error at CMakeLists.txt:24 (add_executable):
  add_executable cannot create target "webm_info" because another target with
  the same name already exists.  The existing target is an executable created
  in source directory "/home/relja/Desktop/applicationsAndServices/libwebm".
  See documentation for policy CMP0002 for more details.


CMake Error at CMakeLists.txt:31 (target_link_libraries):
  Attempt to add link library "webm" to target "webm_info" which is not built
  in this directory.


-- Configuring incomplete, errors occurred!
See also "/home/relja/Desktop/applicationsAndServices/webm-tools/CMakeFiles/CMakeOutput.log".
See also "/home/relja/Desktop/applicationsAndServices/webm-tools/CMakeFiles/CMakeError.log".

正如我之前提到的，我在流程的第 2 步中使用了 libwebm。 我尝试删除 libwebm，但我得到的响应是 libwebm 不存在，因此无法执行操作。我尝试过使用 CMakeLists.txt，但由于我不了解这里的根本原因，因此一无所获。文档不存在（或者我找不到）所以我不得不求助于这个。如果我忘了添加什么，请询问。

编辑 1： 忘了说，我用的是ubuntu 编辑2： 通过使用 unix makefile 而不是 cmake 避免了这个问题，工作正常

Answer 1

我花了一段时间摆弄这个并想出了一个有效的 CMakeLists.txt：

##  Copyright (c) 2015 The WebM project authors. All Rights Reserved.
##
##  Use of this source code is governed by a BSD-style license
##  that can be found in the LICENSE file in the root of the source
##  tree. An additional intellectual property rights grant can be found
##  in the file PATENTS.  All contributing project authors may
##  be found in the AUTHORS file in the root of the source tree.
cmake_minimum_required(VERSION 2.8)
project(WEBMTOOLS)

set(WEBMTOOLS_SRC_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
# TODO(tomfinegan): The libwebm source directory must be configurable.
set(LIBWEBM_SRC_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../libwebm")
# This is where LIBWEBM targets are built.
set(LIBWEBM_BUILD_DIR "${CMAKE_BINARY_DIR}/libwebm_build")

# Libwebm section.
# Add the libwebm CMakeLists.txt and set the binary dir to allow access to
# libwebm build output.
add_subdirectory("${LIBWEBM_SRC_DIR}" "${LIBWEBM_BUILD_DIR}")
include_directories("${LIBWEBM_SRC_DIR}"
                    "${WEBMTOOLS_SRC_DIR}/shared")

add_executable(dash_manifest
  "${WEBMTOOLS_SRC_DIR}/shared/indent.cc"
  "${WEBMTOOLS_SRC_DIR}/shared/webm_file.cc"
  "${WEBMTOOLS_SRC_DIR}/shared/webm_incremental_reader.cc"
  "${WEBMTOOLS_SRC_DIR}/webm_dash_manifest/adaptation_set.cc"
  "${WEBMTOOLS_SRC_DIR}/webm_dash_manifest/dash_model.cc"
  "${WEBMTOOLS_SRC_DIR}/webm_dash_manifest/period.cc"
  "${WEBMTOOLS_SRC_DIR}/webm_dash_manifest/representation.cc"
  "${WEBMTOOLS_SRC_DIR}/webm_dash_manifest/webm_dash_manifest.cc")

target_link_libraries(dash_manifest LINK_PUBLIC webm)

为了编译 webm_dash_manifest：

cd webm_dash_manifest/
make

另请注意，sample_muxer 现在称为 mkvmuxer_sample。