c# - 如何使用 C# 创建视频缩略图

Question

我找到了一些文章，一些项目来创建视频的缩略图，使用 ffmpeg.exe，表达式编码器，但是当我下载他们不工作的项目时......我没有因为有问题或项目而下载天气 ffmpeg.exe不工作。

如果有人有其他来源我可以看到样品。请张贴。。

-提前致谢

Answer 1

这是使用 ffmpeg.exe 制作视频或图像缩略图的类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
namespace Pariwaar.Controller
{
    public class imageResize
    {

        public byte[] ResizeFromByteArray(int MaxSideSize, Byte[] byteArrayIn, string fileName)
        {
            byte[] byteArray = null;  // really make this an error gif
            MemoryStream ms = new MemoryStream(byteArrayIn);
            byteArray = this.ResizeFromStream(MaxSideSize, ms, fileName);

            return byteArray;
        }

        /// <summary>
        /// converts stream to bytearray for resized image
        /// </summary>
        /// <param name="MaxSideSize"></param>
        /// <param name="Buffer"></param>
        /// <returns></returns>
        public byte[] ResizeFromStream(int MaxSideSize, Stream Buffer, string fileName)
        {
            byte[] byteArray = null;  // really make this an error gif

            try
            {

                Bitmap bitMap = new Bitmap(Buffer);
                int intOldWidth = bitMap.Width;
                int intOldHeight = bitMap.Height;

                int intNewWidth;
                int intNewHeight;

                int intMaxSide;

                if (intOldWidth >= intOldHeight)
                {
                    intMaxSide = intOldWidth;
                }
                else
                {
                    intMaxSide = intOldHeight;
                }

                if (intMaxSide > MaxSideSize)
                {
                    //set new width and height
                    double dblCoef = MaxSideSize / (double)intMaxSide;
                    intNewWidth = Convert.ToInt32(dblCoef * intOldWidth);
                    intNewHeight = Convert.ToInt32(dblCoef * intOldHeight);
                }
                else
                {
                    intNewWidth = intOldWidth;
                    intNewHeight = intOldHeight;
                }

                Size ThumbNailSize = new Size(intNewWidth, intNewHeight);
                System.Drawing.Image oImg = System.Drawing.Image.FromStream(Buffer);
                System.Drawing.Image oThumbNail = new Bitmap(ThumbNailSize.Width, ThumbNailSize.Height);

                Graphics oGraphic = Graphics.FromImage(oThumbNail);
                oGraphic.CompositingQuality = CompositingQuality.HighQuality;
                oGraphic.SmoothingMode = SmoothingMode.HighQuality;
                oGraphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
                Rectangle oRectangle = new Rectangle
                    (0, 0, ThumbNailSize.Width, ThumbNailSize.Height);

                oGraphic.DrawImage(oImg, oRectangle);

                MemoryStream ms = new MemoryStream();
                oThumbNail.Save(ms, ImageFormat.Jpeg);
                byteArray = new byte[ms.Length];
                ms.Position = 0;
                ms.Read(byteArray, 0, Convert.ToInt32(ms.Length));

                oGraphic.Dispose();
                oImg.Dispose();
                ms.Close();
                ms.Dispose();
            }
            catch (Exception)
            {
                int newSize = MaxSideSize - 20;
                Bitmap bitMap = new Bitmap(newSize, newSize);
                Graphics g = Graphics.FromImage(bitMap);
                g.FillRectangle(new SolidBrush(Color.Gray), new Rectangle(0, 0, newSize, newSize));

                Font font = new Font("Courier", 8);
                SolidBrush solidBrush = new SolidBrush(Color.Red);
                g.DrawString("Failed File", font, solidBrush, 10, 5);
                g.DrawString(fileName, font, solidBrush, 10, 50);

                MemoryStream ms = new MemoryStream();
                bitMap.Save(ms, ImageFormat.Jpeg);
                byteArray = new byte[ms.Length];
                ms.Position = 0;
                ms.Read(byteArray, 0, Convert.ToInt32(ms.Length));

                ms.Close();
                ms.Dispose();
                bitMap.Dispose();
                solidBrush.Dispose();
                g.Dispose();
                font.Dispose();

            }
            return byteArray;
        }

        /// <summary>
        /// Saves the resized image to specified file name and path as JPEG
        /// and also returns the bytearray for any other use you may need it for
        /// </summary>
        /// <param name="MaxSideSize"></param>
        /// <param name="Buffer"></param>
        /// <param name="fileName">No Extension</param>
        /// <param name="filePath">Examples: "images/dir1/dir2" or "images" or "images/dir1"</param>
        /// <returns></returns>
        public byte[] SaveFromStream(int MaxSideSize, Stream Buffer, string ErrorMessage, string filePath, string ThumbnailPath)
        {
            byte[] byteArray = null;  // really make this an error gif

            try
            {

                Bitmap bitMap = new Bitmap(Buffer);
                int intOldWidth = bitMap.Width;
                int intOldHeight = bitMap.Height;

                int intNewWidth;
                int intNewHeight;

                int intMaxSide;

                if (intOldWidth >= intOldHeight)
                {
                    intMaxSide = intOldWidth;
                }
                else
                {
                    intMaxSide = intOldHeight;
                }

                if (intMaxSide > MaxSideSize)
                {
                    //set new width and height
                    double dblCoef = MaxSideSize / (double)intMaxSide;
                    intNewWidth = Convert.ToInt32(dblCoef * intOldWidth);
                    intNewHeight = Convert.ToInt32(dblCoef * intOldHeight);
                }
                else
                {
                    intNewWidth = intOldWidth;
                    intNewHeight = intOldHeight;
                }

                Size ThumbNailSize = new Size(intNewWidth, intNewHeight);
                System.Drawing.Image oImg = System.Drawing.Image.FromStream(Buffer);
                System.Drawing.Image oThumbNail = new Bitmap(ThumbNailSize.Width, ThumbNailSize.Height);

                Graphics oGraphic = Graphics.FromImage(oThumbNail);

                oGraphic.CompositingQuality = CompositingQuality.HighQuality;
                oGraphic.SmoothingMode = SmoothingMode.HighQuality;
                oGraphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
                Rectangle oRectangle = new Rectangle
                    (0, 0, ThumbNailSize.Width, ThumbNailSize.Height);

                oGraphic.DrawImage(oImg, oRectangle);

                //Save File
                string newFileName = filePath;
                oThumbNail.Save(newFileName, ImageFormat.Jpeg);

                MemoryStream ms = new MemoryStream();
                oThumbNail.Save(ms, ImageFormat.Jpeg);

                //--- done by vrunda create thmbnail
                System.Drawing.Image.GetThumbnailImageAbort dummyCallBack = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
                System.Drawing.Image thumbNailImg =oThumbNail.GetThumbnailImage(100, 100, dummyCallBack, IntPtr.Zero);
                thumbNailImg.Save(ThumbnailPath, ImageFormat.Jpeg);
                //----- done by vrunda

                byteArray = new byte[ms.Length];
                ms.Position = 0;
                ms.Read(byteArray, 0, Convert.ToInt32(ms.Length));

                oGraphic.Dispose();
                oImg.Dispose();
                ms.Close();
                ms.Dispose();
            }
            catch (Exception)
            {
                int newSize = MaxSideSize - 20;
                Bitmap bitMap = new Bitmap(newSize, newSize);
                Graphics g = Graphics.FromImage(bitMap);
                g.FillRectangle(new SolidBrush(Color.Gray), new Rectangle(0, 0, newSize, newSize));

                Font font = new Font("Courier", 8);
                SolidBrush solidBrush = new SolidBrush(Color.Red);
                g.DrawString("Failed To Save File or Failed File  ", font, solidBrush, 10, 5);
                g.DrawString(ErrorMessage, font, solidBrush, 10, 50);

                MemoryStream ms = new MemoryStream();
                bitMap.Save(ms, ImageFormat.Jpeg);
                byteArray = new byte[ms.Length];
                ms.Position = 0;
                ms.Read(byteArray, 0, Convert.ToInt32(ms.Length));

                ms.Close();
                ms.Dispose();
                bitMap.Dispose();
                solidBrush.Dispose();
                g.Dispose();
                font.Dispose();

            }
            return byteArray;
        }
        public bool ThumbnailCallback()
        {
            return false;
        }

    }
}

Answer 2

这是工作ffmpeg示例的链接

http://www.codeproject.com/Articles/241399/Convert-Video-to-Flash-Video-flv-and-progressive-s

希望这可以帮助你