ffmpeg开源库，实现将bmp格式的图片编码成x264文件，并将编码好的H264文件解码保存为BMP文件。

实现将视频文件yuv格式保存的图片格式的测试，图像格式png,jpg, gif等等测试均OK

 

  自己根据博客的代码，vs2010搭建的测试环境。资源下载 

   具体代码：

 

1. #define _AFXDLL

2. #include<afxwin.h>

3. #ifdef __cplusplus

4. extern "C" {

5. #endif

6.  

7. #include <libavcodec/avcodec.h>

8. #include <libavformat/avformat.h>

9. #include <libswscale/swscale.h>

10. void main()

11. {

12. CFile file[5];

13. BYTE *szTxt[5];

14.  

15. int nWidth = 0;

16. int nHeight= 0;

17.  

18. int nDataLen=0;

19.  

20. int nLen;

21.  

22. CString csFileName;

23. for (int fileI = 1; fileI <= 5; fileI ++)

24. {

25. csFileName.Format("%d.bmp", fileI);

26. file[fileI - 1].Open(csFileName,CFile::modeRead | CFile::typeBinary);

27. nLen = file[fileI - 1].GetLength();

28.  

29. szTxt[fileI -1] = new BYTE[nLen];

30. file[fileI - 1].Read(szTxt[fileI - 1], nLen);

31. file[fileI - 1].Close();

32.  

33. //BMP bmi;//BITMAPINFO bmi;

34. //int nHeadLen = sizeof(BMP);

35. BITMAPFILEHEADER bmpFHeader;

36. BITMAPINFOHEADER bmpIHeader;

37. memcpy(&bmpFHeader,szTxt[fileI -1],sizeof(BITMAPFILEHEADER));

38.  

39. int nHeadLen = bmpFHeader.bfOffBits - sizeof(BITMAPFILEHEADER);

40. memcpy(&bmpIHeader,szTxt[fileI - 1]+sizeof(BITMAPFILEHEADER),nHeadLen);

41.  

42. nWidth = bmpIHeader.biWidth;// 464;// bmi.bmpInfo.bmiHeader.biWidth;// ;

43. nHeight = bmpIHeader.biHeight;//362;// bmi.bmpInfo.bmiHeader.biHeight;// ;

44.  

45. szTxt[fileI - 1] += bmpFHeader.bfOffBits;

46. nDataLen = nLen-bmpFHeader.bfOffBits;

47. }

48. getchar();

49. av_register_all();

50. avcodec_register_all();

51. AVFrame *m_pRGBFrame = new AVFrame[1]; //RGB帧数据

52. AVFrame *m_pYUVFrame = new AVFrame[1];; //YUV帧数据

53. AVCodecContext *c= NULL;

54. AVCodecContext *in_c= NULL;

55. AVCodec *pCodecH264; //编码器

56. uint8_t * yuv_buff;//

57.  

58. //查找h264编码器

59. pCodecH264 = avcodec_find_encoder(CODEC_ID_H264);

60. if(!pCodecH264)

61. {

62. fprintf(stderr, "h264 codec not found\n");

63. getchar();

64. exit(1);

65. }

66.  

67. c= avcodec_alloc_context3(pCodecH264);

68. c->bit_rate = 3000000;// put sample parameters

69. c->width =nWidth;//

70. c->height = nHeight;//

71.  

72. // frames per second

73. AVRational rate;

74. rate.num = 1;

75. rate.den = 25;

76. c->time_base= rate;//(AVRational){1,25};

77. c->gop_size = 10; // emit one intra frame every ten frames

78. c->max_b_frames=1;

79. c->thread_count = 1;

80. c->pix_fmt = PIX_FMT_YUV420P;//PIX_FMT_RGB24;

81.  

82. //av_opt_set(c->priv_data, /*"preset"*/"libvpx-1080p.ffpreset", /*"slow"*/NULL, 0);

83. //打开编码器

84. if(avcodec_open2(c,pCodecH264,NULL)<0){

85. printf("avcodec_open2 failed\n");

86. TRACE("不能打开编码库");

87. getchar();

88. }

89.  

90. int size = c->width * c->height;

91.  

92. yuv_buff = (uint8_t *) malloc((size * 3) / 2); // size for YUV 420

93.  

94. //将rgb图像数据填充rgb帧

95. uint8_t * rgb_buff = new uint8_t[nDataLen];

96.  

97. //图象编码 outbuf_size太小会报错，图像清晰度也会差

98. int outbuf_size = 900000;

99. uint8_t * outbuf= (uint8_t*)malloc(outbuf_size);

100. int u_size = 0;

101. FILE *f=NULL;

102. char * filename = "myData.h264";

103. f = fopen(filename, "wb");

104. if (!f)

105. {

106. TRACE( "could not open %s\n", filename);

107. getchar();

108. exit(1);

109. }

110.  

111. //初始化SwsContext

112. SwsContext * scxt = sws_getContext(c->width,c->height,PIX_FMT_BGR24,c->width,c->height,PIX_FMT_YUV420P,SWS_POINT,NULL,NULL,NULL);

113.  

114. AVPacket avpkt;

115.  

116. //AVFrame *pTFrame=new AVFrame

117. for (int i=0;i<250;++i)

118. {

119.  

120. //AVFrame *m_pYUVFrame = new AVFrame[1];

121.  

122. int index = (i / 25) % 5;

123. memcpy(rgb_buff,szTxt[index],nDataLen);

124.  

125. avpicture_fill((AVPicture*)m_pRGBFrame, (uint8_t*)rgb_buff, PIX_FMT_RGB24, nWidth, nHeight);

126.  

127. //将YUV buffer 填充YUV Frame

128. avpicture_fill((AVPicture*)m_pYUVFrame, (uint8_t*)yuv_buff, PIX_FMT_YUV420P, nWidth, nHeight);

129.  

130. // 翻转RGB图像

131. m_pRGBFrame->data[0] += m_pRGBFrame->linesize[0] * (nHeight - 1);

132. m_pRGBFrame->linesize[0] *= -1;

133. m_pRGBFrame->data[1] += m_pRGBFrame->linesize[1] * (nHeight / 2 - 1);

134. m_pRGBFrame->linesize[1] *= -1;

135. m_pRGBFrame->data[2] += m_pRGBFrame->linesize[2] * (nHeight / 2 - 1);

136. m_pRGBFrame->linesize[2] *= -1;

137.  
138.  

139. //将RGB转化为YUV

140. sws_scale(scxt,m_pRGBFrame->data,m_pRGBFrame->linesize,0,c->height,m_pYUVFrame->data,m_pYUVFrame->linesize);

141.  

142. static int got_packet_ptr = 0;

143. av_init_packet(&avpkt);

144. avpkt.data = outbuf;

145. avpkt.size = outbuf_size;

146. u_size = avcodec_encode_video2(c, &avpkt, m_pYUVFrame, &got_packet_ptr);

147. m_pYUVFrame->pts++;

148. if (u_size == 0)

149. {

150. fwrite(avpkt.data, 1, avpkt.size, f);

151. }

152. }

153.  

154. fclose(f);

155. delete []m_pRGBFrame;

156. delete []m_pYUVFrame;

157. delete []rgb_buff;

158. free(outbuf);

159. avcodec_close(c);

160. av_free(c);

161.  

162. }

163.  

164. #ifdef __cplusplus

165. }

166. #endif

 完全按照博客中的代码测试发现会报下面的信息，而且在播放过程中，画面都是模糊的。修改了outbuff_size的大小解决了这个问题。

 

 

疑问：为什么要循环250次？有知道麻烦解答下！

for (int i=0;i<250;++i)

将H264视频保存为BMP图片，具体代码如下：

1. #include <stdio.h>

2. #include <stdlib.h>

3. #include <string.h>

4. #include <windows.h>

5.  

6. #ifdef __cplusplus

7. extern "C" {

8. #endif

9.  

10. #include <libavcodec/avcodec.h>

11. #include <libavformat/avformat.h>

12. #include <libswscale/swscale.h>

13.  

14. void SaveAsBMP (AVFrame *pFrameRGB, int width, int height, int index, int bpp)

15. {

16. char buf[5] = {0};

17. BITMAPFILEHEADER bmpheader;

18. BITMAPINFOHEADER bmpinfo;

19. FILE *fp;

20.  

21. char filename[20] = "";

22. _itoa (index, buf, 10);

23. strcat (filename, buf);

24. strcat (filename, ".bmp");

25.  

26. if ( (fp = fopen(filename,"wb+")) == NULL )

27. {

28. printf ("open file failed!\n");

29. return;

30. }

31.  

32. bmpheader.bfType = 0x4d42;

33. bmpheader.bfReserved1 = 0;

34. bmpheader.bfReserved2 = 0;

35. bmpheader.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);

36. bmpheader.bfSize = bmpheader.bfOffBits + width*height*bpp/8;

37.  

38. bmpinfo.biSize = sizeof(BITMAPINFOHEADER);

39. bmpinfo.biWidth = width;

40. bmpinfo.biHeight = height;

41. bmpinfo.biPlanes = 1;

42. bmpinfo.biBitCount = bpp;

43. bmpinfo.biCompression = BI_RGB;

44. bmpinfo.biSizeImage = (width*bpp+31)/32*4*height;

45. bmpinfo.biXPelsPerMeter = 100;

46. bmpinfo.biYPelsPerMeter = 100;

47. bmpinfo.biClrUsed = 0;

48. bmpinfo.biClrImportant = 0;

49.  

50. fwrite (&bmpheader, sizeof(bmpheader), 1, fp);

51. fwrite (&bmpinfo, sizeof(bmpinfo), 1, fp);

52. fwrite (pFrameRGB->data[0], width*height*bpp/8, 1, fp);

53.  

54. fclose(fp);

55. }

56.  
57.  

58. int main (void)

59. {

60. unsigned int i = 0, videoStream = -1;

61. AVCodecContext *pCodecCtx;

62. AVFormatContext *pFormatCtx = NULL;

63. AVCodec *pCodec;

64. AVFrame *pFrame, *pFrameRGB;

65. struct SwsContext *pSwsCtx;

66. const char *filename = "myData.h264";

67. AVPacket packet;

68. int frameFinished;

69. int PictureSize;

70. uint8_t *buf;

71.  

72. av_register_all();

73.  

74. if (avformat_open_input(&pFormatCtx, filename, NULL, NULL) != 0 ){

75. printf ("av open input file failed!\n");

76. exit (1);

77. }

78.  

79. if ( avformat_find_stream_info(pFormatCtx,NULL) < 0 ){

80. printf ("av find stream info failed!\n");

81. exit (1);

82. }

83.  

84. for ( i=0; i<pFormatCtx->nb_streams; i++ ){

85. if ( pFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO ){

86. videoStream = i;

87. break;

88. }

89. }

90.  

91. if (videoStream == -1){

92. printf ("find video stream failed!\n");

93. exit (1);

94. }

95.  

96. pCodecCtx = pFormatCtx->streams[videoStream]->codec;

97.  

98. pCodec = avcodec_find_decoder (pCodecCtx->codec_id);

99. if (pCodec == NULL){

100. printf ("avcode find decoder failed!\n");

101. exit (1);

102. }

103.  
104.  
105.  
106.  

107. if ( avcodec_open2(pCodecCtx, pCodec,NULL)<0 ){

108. printf ("avcode open failed!\n");

109. exit (1);

110. }

111.  

112. pFrame = avcodec_alloc_frame();

113. pFrameRGB = avcodec_alloc_frame();

114.  

115. if ( (pFrame == NULL)||(pFrameRGB == NULL) ){

116. printf("avcodec alloc frame failed!\n");

117. exit (1);

118. }

119.  

120. PictureSize = avpicture_get_size (PIX_FMT_BGR24, pCodecCtx->width, pCodecCtx->height);

121.  

122. buf = (uint8_t *)av_malloc(PictureSize);

123.  

124. if ( buf == NULL ){

125. printf( "av malloc failed!\n");

126. exit(1);

127. }

128.  

129. avpicture_fill ( (AVPicture *)pFrameRGB, buf, PIX_FMT_BGR24, pCodecCtx->width, pCodecCtx->height);

130.  

131. pSwsCtx = sws_getContext (pCodecCtx->width,

132. pCodecCtx->height,

133. pCodecCtx->pix_fmt,

134. pCodecCtx->width,

135. pCodecCtx->height,

136. PIX_FMT_BGR24,

137. SWS_BICUBIC,

138. NULL, NULL, NULL);

139.  

140. i = 0;

141.  

142. while(av_read_frame(pFormatCtx, &packet) >= 0){

143. if(packet.stream_index == videoStream){

144. avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);

145.  

146. if(frameFinished){

147. //反转图像

148. pFrame->data[0] += pFrame->linesize[0] * (pCodecCtx->height - 1);

149. pFrame->linesize[0] *= -1;

150. pFrame->data[1] += pFrame->linesize[1] * (pCodecCtx->height / 2 - 1);

151. pFrame->linesize[1] *= -1;

152. pFrame->data[2] += pFrame->linesize[2] * (pCodecCtx->height / 2 - 1);

153. pFrame->linesize[2] *= -1;

154.  

155. sws_scale (pSwsCtx, pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);

156.  

157. SaveAsBMP (pFrameRGB, pCodecCtx->width, pCodecCtx->height, i++, 24);

158. }

159. }

160. av_free_packet(&packet);

161. }

162.  

163. while(1){

164. packet.data = NULL;

165. packet.size = 0;

166. avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);

167.  

168. if(frameFinished){

169. //反转图像

170. pFrame->data[0] += pFrame->linesize[0] * (pCodecCtx->height - 1);

171. pFrame->linesize[0] *= -1;

172. pFrame->data[1] += pFrame->linesize[1] * (pCodecCtx->height / 2 - 1);

173. pFrame->linesize[1] *= -1;

174. pFrame->data[2] += pFrame->linesize[2] * (pCodecCtx->height / 2 - 1);

175. pFrame->linesize[2] *= -1;

176.  

177. sws_scale (pSwsCtx, pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize);

178.  

179. SaveAsBMP (pFrameRGB, pCodecCtx->width, pCodecCtx->height, i++, 24);

180. }else{

181. break;

182. }

183.  

184. av_free_packet(&packet);

185. }

186.  

187. sws_freeContext (pSwsCtx);

188. av_free (pFrame);

189. av_free (pFrameRGB);

190. avcodec_close (pCodecCtx);

191. avformat_close_input (&pFormatCtx);

192.  

193. return 0;

194. }

195.  

196. #ifdef __cplusplus

197. }

198. #endif

 

视频文件保存图片的另外一个方法，看代码

1. /*File : yuv2pic

2. *Auth : sjin

3. *Date : 20141123

4. *Mail : 413977243@qq.com

5. */

6.  

7. /*

8. * 参考博客http://blog.csdn.net/leixiaohua1020/article/details/25346147

9. *本程序实现了YUV420P像素数据编码为JPEG图片。是最简单的FFmpeg编码方面的教程。

10. *通过学习本例子可以了解FFmpeg的编码流程。

11. */

12. #include <libavcodec/avcodec.h>

13. #include <libavformat/avformat.h>

14. #include <libswscale/swscale.h>

15.  

16. #define INPUT_FILE_NAME "yuv420p.yuv"

17. #define OUTPUT_FILE_NAME "encode.png"

18. #define INPUT_FILE_WDITH 176

19. #define INPUT_FILE_HEIGHT 144

20.  

21. int main(int argc, char* argv[])

22. {

23. AVFormatContext* pFormatCtx;

24. AVOutputFormat* fmt;

25. AVStream* video_st;

26. AVCodecContext* pCodecCtx;

27. AVCodec* pCodec;

28.  

29. uint8_t* picture_buf;

30. AVFrame* picture;

31. int size;

32.  

33. FILE *in_file = fopen(INPUT_FILE_NAME, "rb"); //视频YUV源文件

34. int in_w = INPUT_FILE_WDITH;

35. int in_h = INPUT_FILE_HEIGHT; //宽高

36. const char* out_file = OUTPUT_FILE_NAME; //输出文件路径

37.  

38. av_register_all();

39. #if 0

40. //方法1.组合使用几个函数

41. pFormatCtx = avformat_alloc_context();

42. //猜格式。用MJPEG编码

43. fmt = av_guess_format("mjpeg", NULL, NULL);

44. pFormatCtx->oformat = fmt;

45. //注意：输出路径

46. if (avio_open(&pFormatCtx->pb,out_file, AVIO_FLAG_READ_WRITE) < 0){

47. printf("输出文件打开失败");

48. return -1;

49. }

50. #else

51. //方法2.更加自动化一些

52. //分配一个输出（out_file）文件格式的AVFormatContext的上下文句柄

53. avformat_alloc_output_context2(&pFormatCtx, NULL, NULL, out_file);

54. fmt = pFormatCtx->oformat;

55.  

56. video_st = avformat_new_stream(pFormatCtx,NULL);

57. if (video_st==NULL){

58. return -1;

59. }

60. #endif

61. pCodecCtx = video_st->codec;

62. pCodecCtx->codec_id = fmt->video_codec;

63. pCodecCtx->codec_type = AVMEDIA_TYPE_VIDEO;

64. pCodecCtx->pix_fmt = PIX_FMT_YUVJ420P;

65.  

66. pCodecCtx->width = in_w;

67. pCodecCtx->height = in_h;

68.  

69. pCodecCtx->time_base.num = 1;

70. pCodecCtx->time_base.den = 25;

71. //输出格式信息

72. av_dump_format(pFormatCtx, 0, out_file, 1);

73.  

74. pCodec = avcodec_find_encoder(pCodecCtx->codec_id);

75. if (!pCodec){

76. printf("没有找到合适的编码器！");

77. return -1;

78. }

79. if (avcodec_open2(pCodecCtx, pCodec,NULL) < 0){

80. printf("编码器打开失败！");

81. return -1;

82. }

83.  

84. //申请解码后保存视频帧的空间，AVFrame结构体

85. picture = avcodec_alloc_frame();

86. //即使我们申请的一帧的内存，当转换的时候，我们仍需要内存去保存原始的数据

87. //利用下面的函数来获得原始数据帧的大小，手动分配内存

88. size = avpicture_get_size(pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height);

89. picture_buf = (uint8_t *)av_malloc(size);

90. if (!picture_buf){

91. return -1;

92. }

93. //设置指定图像的参数，并指着图像数据缓冲区

94. avpicture_fill((AVPicture *)picture, picture_buf, pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height);

95.  

96. //写文件头

97. avformat_write_header(pFormatCtx,NULL);

98.  

99. AVPacket pkt;

100. int y_size = pCodecCtx->width * pCodecCtx->height;

101. av_new_packet(&pkt,y_size*3);

102. //读入YUV

103. if (fread(picture_buf, 1, y_size*3/2, in_file) < 0){

104. printf("文件读取错误");

105. return -1;

106. }

107.  

108. //翻转图像

109. picture->data[0] = picture_buf; // 亮度Y

110. picture->data[1] = picture_buf+ y_size; // U

111. picture->data[2] = picture_buf+ y_size*5/4; // V

112. int got_picture=0;

113. //编码

114. int ret = avcodec_encode_video2(pCodecCtx, &pkt,picture, &got_picture);

115. if(ret < 0){

116. printf("编码错误！\n");

117. return -1;

118. }

119. if (got_picture==1){

120. pkt.stream_index = video_st->index;

121. ret = av_write_frame(pFormatCtx, &pkt);

122. }

123.  

124. av_free_packet(&pkt);

125. //写文件尾

126. av_write_trailer(pFormatCtx);

127.  

128. printf("编码成功！\n");

129.  

130. if (video_st){

131. avcodec_close(video_st->codec);

132. av_free(picture);

133. av_free(picture_buf);

134. }

135.  

136. avio_close(pFormatCtx->pb);

137. avformat_free_context(pFormatCtx);

138.  

139. fclose(in_file);

140.  

141. return 0;

142. }

下面是编译的时候，比较好用的Makefile文件

1. # use pkg-config for getting CFLAGS and LDLIBS

2. FFMPEG_LIBS= libavdevice \

3. libavformat \

4. libavfilter \

5. libavcodec \

6. libswresample \

7. libswscale \

8. libavutil \

9.  

10. CFLAGS += -Wall -O2 -g

11. CFLAGS := $(shell pkg-config --cflags $(FFMPEG_LIBS)) $(CFLAGS)

12. LDLIBS := $(shell pkg-config --libs $(FFMPEG_LIBS)) $(LDLIBS)

13.  

14. EXAMPLES= yuv2pic

15.  

16. OBJS=$(addsuffix .o,$(EXAMPLES))

17.  

18. # the following examples make explicit use of the math library

19. LDLIBS += -lx264 -m32 -pthread -lm -ldl

20.  

21. .phony:all clean

22.  

23. all: $(OBJS) $(EXAMPLES)

24.  

25. clean:

26. rm $(EXAMPLES) $(OBJS)

 

参考资料：

1、http://blog.csdn.net/eightdegree/article/details/7425635#reply

2、http://blog.csdn.net/leixiaohua1020/article/details/25346147