examples/avcodec: split the remaining two examples into separate files

configure

@@ -1209,9 +1209,10 @@ COMPONENT_LIST="
 "
 
 EXAMPLE_LIST="
-    avcodec_example
     decode_audio_example
+    decode_video_example
     encode_audio_example
+    encode_video_example
     filter_audio_example
     metadata_example
     output_example
@@ -2436,9 +2437,10 @@ scale_qsv_filter_deps="libmfx"
 scale_vaapi_filter_deps="vaapi VAProcPipelineParameterBuffer"
 
 # examples
-avcodec_example_deps="avcodec avutil"
 decode_audio_example_deps="avcodec avutil"
+decode_video_example_deps="avcodec avutil"
 encode_audio_example_deps="avcodec avutil"
+encode_video_example_deps="avcodec avutil"
 filter_audio_example_deps="avfilter avutil"
 metadata_example_deps="avformat avutil"
 output_example_deps="avcodec avformat avutil swscale"

doc/Makefile

@@ -16,16 +16,22 @@ DOCS-$(CONFIG_POD2MAN)                          += $(MANPAGES) $(PODPAGES)
 DOCS-$(CONFIG_TEXI2HTML)                        += $(HTMLPAGES)
 DOCS = $(DOCS-yes)
 
-DOC_EXAMPLES-$(CONFIG_AVCODEC_EXAMPLE)          += avcodec
 DOC_EXAMPLES-$(CONFIG_DECODE_AUDIO_EXAMPLE)     += decode_audio
+DOC_EXAMPLES-$(CONFIG_DECODE_VIDEO_EXAMPLE)     += decode_video
 DOC_EXAMPLES-$(CONFIG_ENCODE_AUDIO_EXAMPLE)     += encode_audio
+DOC_EXAMPLES-$(CONFIG_ENCODE_VIDEO_EXAMPLE)     += encode_video
 DOC_EXAMPLES-$(CONFIG_FILTER_AUDIO_EXAMPLE)     += filter_audio
 DOC_EXAMPLES-$(CONFIG_METADATA_EXAMPLE)         += metadata
 DOC_EXAMPLES-$(CONFIG_OUTPUT_EXAMPLE)           += output
 DOC_EXAMPLES-$(CONFIG_QSVDEC_EXAMPLE)           += qsvdec
 DOC_EXAMPLES-$(CONFIG_TRANSCODE_AAC_EXAMPLE)    += transcode_aac
-ALL_DOC_EXAMPLES = avcodec decode_audio encode_audio filter_audio metadata \
-                   output transcode_aac
+ALL_DOC_EXAMPLES = decode_audio                                         \
+                   decode_video                                         \
+                   encode_audio                                         \
+                   encode_video                                         \
+                   filter_audio                                         \
+                   metadata output                                      \
+                   transcode_aac                                        \
 
 DOC_EXAMPLES     := $(DOC_EXAMPLES-yes:%=doc/examples/%$(EXESUF))
 ALL_DOC_EXAMPLES := $(ALL_DOC_EXAMPLES:%=doc/examples/%$(EXESUF))

doc/examples/avcodec.c → doc/examples/decode_video.c

@@ -20,159 +20,23 @@
 
 /**
  * @file
- * libavcodec API use example.
+ * video decoding with libavcodec API example
  *
- * @example avcodec.c
- * Note that this library only handles codecs (MPEG, MPEG-4, etc...),
- * not file formats (AVI, VOB, etc...). See library 'libavformat' for the
- * format handling.
+ * @example decode_video.c
  */
 
-#include <stdlib.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 
-#ifdef HAVE_AV_CONFIG_H
-#undef HAVE_AV_CONFIG_H
-#endif
-
 #include "libavcodec/avcodec.h"
-#include "libavutil/channel_layout.h"
+
 #include "libavutil/common.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/mathematics.h"
-#include "libavutil/samplefmt.h"
 
 #define INBUF_SIZE 4096
 
-/*
- * Video encoding example
- */
-static void video_encode_example(const char *filename)
-{
-    AVCodec *codec;
-    AVCodecContext *c= NULL;
-    int i, ret, x, y, got_output;
-    FILE *f;
-    AVFrame *picture;
-    AVPacket pkt;
-    uint8_t endcode[] = { 0, 0, 1, 0xb7 };
-
-    printf("Video encoding\n");
-
-    /* find the mpeg1video encoder */
-    codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO);
-    if (!codec) {
-        fprintf(stderr, "codec not found\n");
-        exit(1);
-    }
-
-    c = avcodec_alloc_context3(codec);
-    picture = av_frame_alloc();
-
-    /* put sample parameters */
-    c->bit_rate = 400000;
-    /* resolution must be a multiple of two */
-    c->width = 352;
-    c->height = 288;
-    /* frames per second */
-    c->time_base= (AVRational){1,25};
-    c->gop_size = 10; /* emit one intra frame every ten frames */
-    c->max_b_frames=1;
-    c->pix_fmt = AV_PIX_FMT_YUV420P;
-
-    /* open it */
-    if (avcodec_open2(c, codec, NULL) < 0) {
-        fprintf(stderr, "could not open codec\n");
-        exit(1);
-    }
-
-    f = fopen(filename, "wb");
-    if (!f) {
-        fprintf(stderr, "could not open %s\n", filename);
-        exit(1);
-    }
-
-    ret = av_image_alloc(picture->data, picture->linesize, c->width, c->height,
-                         c->pix_fmt, 32);
-    if (ret < 0) {
-        fprintf(stderr, "could not alloc raw picture buffer\n");
-        exit(1);
-    }
-    picture->format = c->pix_fmt;
-    picture->width  = c->width;
-    picture->height = c->height;
-
-    /* encode 1 second of video */
-    for(i=0;i<25;i++) {
-        av_init_packet(&pkt);
-        pkt.data = NULL;    // packet data will be allocated by the encoder
-        pkt.size = 0;
-
-        fflush(stdout);
-        /* prepare a dummy image */
-        /* Y */
-        for(y=0;y<c->height;y++) {
-            for(x=0;x<c->width;x++) {
-                picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
-            }
-        }
-
-        /* Cb and Cr */
-        for(y=0;y<c->height/2;y++) {
-            for(x=0;x<c->width/2;x++) {
-                picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
-                picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
-            }
-        }
-
-        picture->pts = i;
-
-        /* encode the image */
-        ret = avcodec_encode_video2(c, &pkt, picture, &got_output);
-        if (ret < 0) {
-            fprintf(stderr, "error encoding frame\n");
-            exit(1);
-        }
-
-        if (got_output) {
-            printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
-            fwrite(pkt.data, 1, pkt.size, f);
-            av_packet_unref(&pkt);
-        }
-    }
-
-    /* get the delayed frames */
-    for (got_output = 1; got_output; i++) {
-        fflush(stdout);
-
-        ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
-        if (ret < 0) {
-            fprintf(stderr, "error encoding frame\n");
-            exit(1);
-        }
-
-        if (got_output) {
-            printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
-            fwrite(pkt.data, 1, pkt.size, f);
-            av_packet_unref(&pkt);
-        }
-    }
-
-    /* add sequence end code to have a real MPEG file */
-    fwrite(endcode, 1, sizeof(endcode), f);
-    fclose(f);
-
-    avcodec_free_context(&c);
-    av_freep(&picture->data[0]);
-    av_frame_free(&picture);
-    printf("\n");
-}
-
-/*
- * Video decoding example
- */
-
 static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,
                      char *filename)
 {
@@ -186,8 +50,9 @@ static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,
     fclose(f);
 }
 
-static void video_decode_example(const char *outfilename, const char *filename)
+int main(int argc, char **argv)
 {
+    const char *filename, *outfilename;
     AVCodec *codec;
     AVCodecContext *c= NULL;
     int frame, got_picture, len;
@@ -197,13 +62,20 @@ static void video_decode_example(const char *outfilename, const char *filename)
     char buf[1024];
     AVPacket avpkt;
 
+    if (argc <= 2) {
+        fprintf(stderr, "Usage: %s <input file> <output file>\n", argv[0]);
+        exit(0);
+    }
+    filename    = argv[1];
+    outfilename = argv[2];
+
+    avcodec_register_all();
+
     av_init_packet(&avpkt);
 
     /* set end of buffer to 0 (this ensures that no overreading happens for damaged MPEG streams) */
     memset(inbuf + INBUF_SIZE, 0, AV_INPUT_BUFFER_PADDING_SIZE);
 
-    printf("Video decoding\n");
-
     /* find the MPEG-1 video decoder */
     codec = avcodec_find_decoder(AV_CODEC_ID_MPEG1VIDEO);
     if (!codec) {
@@ -301,24 +173,6 @@ static void video_decode_example(const char *outfilename, const char *filename)
 
     avcodec_free_context(&c);
     av_frame_free(&picture);
-    printf("\n");
-}
-
-int main(int argc, char **argv)
-{
-    const char *filename;
-
-    /* register all the codecs */
-    avcodec_register_all();
-
-    if (argc <= 1) {
-        video_encode_example("/tmp/test.mpg");
-        filename = "/tmp/test.mpg";
-    } else {
-        filename = argv[1];
-    }
-
-    video_decode_example("/tmp/test%d.pgm", filename);
 
     return 0;
 }

doc/examples/encode_video.c

@@ -0,0 +1,164 @@
+/*
+ * copyright (c) 2001 Fabrice Bellard
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * video encoding with libavcodec API example
+ *
+ * @example encode_video.c
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "libavcodec/avcodec.h"
+
+#include "libavutil/frame.h"
+#include "libavutil/imgutils.h"
+
+int main(int argc, char **argv)
+{
+    const char *filename;
+    AVCodec *codec;
+    AVCodecContext *c= NULL;
+    int i, ret, x, y, got_output;
+    FILE *f;
+    AVFrame *picture;
+    AVPacket pkt;
+    uint8_t endcode[] = { 0, 0, 1, 0xb7 };
+
+    if (argc <= 1) {
+        fprintf(stderr, "Usage: %s <output file>\n", argv[0]);
+        exit(0);
+    }
+    filename = argv[1];
+
+    avcodec_register_all();
+
+    /* find the mpeg1video encoder */
+    codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO);
+    if (!codec) {
+        fprintf(stderr, "codec not found\n");
+        exit(1);
+    }
+
+    c = avcodec_alloc_context3(codec);
+    picture = av_frame_alloc();
+
+    /* put sample parameters */
+    c->bit_rate = 400000;
+    /* resolution must be a multiple of two */
+    c->width = 352;
+    c->height = 288;
+    /* frames per second */
+    c->time_base= (AVRational){1,25};
+    c->gop_size = 10; /* emit one intra frame every ten frames */
+    c->max_b_frames=1;
+    c->pix_fmt = AV_PIX_FMT_YUV420P;
+
+    /* open it */
+    if (avcodec_open2(c, codec, NULL) < 0) {
+        fprintf(stderr, "could not open codec\n");
+        exit(1);
+    }
+
+    f = fopen(filename, "wb");
+    if (!f) {
+        fprintf(stderr, "could not open %s\n", filename);
+        exit(1);
+    }
+
+    ret = av_image_alloc(picture->data, picture->linesize, c->width, c->height,
+                         c->pix_fmt, 32);
+    if (ret < 0) {
+        fprintf(stderr, "could not alloc raw picture buffer\n");
+        exit(1);
+    }
+    picture->format = c->pix_fmt;
+    picture->width  = c->width;
+    picture->height = c->height;
+
+    /* encode 1 second of video */
+    for(i=0;i<25;i++) {
+        av_init_packet(&pkt);
+        pkt.data = NULL;    // packet data will be allocated by the encoder
+        pkt.size = 0;
+
+        fflush(stdout);
+        /* prepare a dummy image */
+        /* Y */
+        for(y=0;y<c->height;y++) {
+            for(x=0;x<c->width;x++) {
+                picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
+            }
+        }
+
+        /* Cb and Cr */
+        for(y=0;y<c->height/2;y++) {
+            for(x=0;x<c->width/2;x++) {
+                picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
+                picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
+            }
+        }
+
+        picture->pts = i;
+
+        /* encode the image */
+        ret = avcodec_encode_video2(c, &pkt, picture, &got_output);
+        if (ret < 0) {
+            fprintf(stderr, "error encoding frame\n");
+            exit(1);
+        }
+
+        if (got_output) {
+            printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
+            fwrite(pkt.data, 1, pkt.size, f);
+            av_packet_unref(&pkt);
+        }
+    }
+
+    /* get the delayed frames */
+    for (got_output = 1; got_output; i++) {
+        fflush(stdout);
+
+        ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
+        if (ret < 0) {
+            fprintf(stderr, "error encoding frame\n");
+            exit(1);
+        }
+
+        if (got_output) {
+            printf("encoding frame %3d (size=%5d)\n", i, pkt.size);
+            fwrite(pkt.data, 1, pkt.size, f);
+            av_packet_unref(&pkt);
+        }
+    }
+
+    /* add sequence end code to have a real MPEG file */
+    fwrite(endcode, 1, sizeof(endcode), f);
+    fclose(f);
+
+    avcodec_free_context(&c);
+    av_freep(&picture->data[0]);
+    av_frame_free(&picture);
+
+    return 0;
+}