[tracker] Improve detection of media stream properties.

[Philip Van Hoof <pvanhoof src gnome org>]

commit ba3cabd67c4473ff6909bc5f6519144b969c98a2
Author: Andrew den Exter <andrew den exter jollamobile com>
Date:   Fri Nov 22 07:12:07 2013 +0000

    Improve detection of media stream properties.
    
    Use the much more comprehensive avformat_stream_info to probe
    data from packetized data rather than directly trying to partially
    decode frames.

 src/tracker-extract/tracker-extract-libav.c |   69 ++-------------------------
 1 files changed, 4 insertions(+), 65 deletions(-)
---
diff --git a/src/tracker-extract/tracker-extract-libav.c b/src/tracker-extract/tracker-extract-libav.c
index 3c71807..ebcd1ba 100644
--- a/src/tracker-extract/tracker-extract-libav.c
+++ b/src/tracker-extract/tracker-extract-libav.c
@@ -123,8 +123,6 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
        AVFormatContext *format = NULL;
        AVStream *audio_stream = NULL;
        AVStream *video_stream = NULL;
-       AVCodec *audio_codec = NULL;
-       AVCodec *video_codec = NULL;
        int audio_stream_index;
        int video_stream_index;
        AVDictionaryEntry *tag = NULL;
@@ -146,12 +144,14 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
        }
        g_free (absoluteFilePath);
 
-       audio_stream_index = av_find_best_stream (format, AVMEDIA_TYPE_AUDIO, -1, -1, &audio_codec, 0);
+       avformat_find_stream_info (format, NULL);
+
+       audio_stream_index = av_find_best_stream (format, AVMEDIA_TYPE_AUDIO, -1, -1, NULL, 0);
        if (audio_stream_index >= 0) {
                audio_stream = format->streams[audio_stream_index];
        }
 
-       video_stream_index = av_find_best_stream (format, AVMEDIA_TYPE_VIDEO, -1, -1, &video_codec, 0);
+       video_stream_index = av_find_best_stream (format, AVMEDIA_TYPE_VIDEO, -1, -1, NULL, 0);
        if (video_stream_index >= 0) {
                video_stream = format->streams[video_stream_index];
        }
@@ -164,36 +164,6 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
        if (audio_stream) {
                if (audio_stream->codec->sample_rate > 0) {
                        set_value_int64 (metadata, "nfo:sampleRate", audio_stream->codec->sample_rate);
-               } else if (avcodec_open2(audio_stream->codec, audio_codec, 0) >= 0) {
-                       AVFrame *frame;
-                       AVPacket packet;
-                       av_init_packet(&packet);
-
-                       frame = avcodec_alloc_frame();
-
-                       for (;;) {
-                               int decoded = 0;
-                               if (av_read_frame (format, &packet) < 0) {
-                                       break;
-                               } else if (packet.stream_index != audio_stream_index) {
-                               } else if (!avcodec_decode_audio4(
-                                       audio_stream->codec, frame, &decoded, &packet) < 0) {
-                                       av_free_packet(&packet);
-                                       break;
-                               } else if (audio_stream->codec->sample_rate > 0) {
-                                       set_value_int64 (metadata, "nfo:sampleRate",
-                                                        audio_stream->codec->sample_rate);
-                                       break;
-                               }
-                               av_free_packet(&packet);
-
-                               if (decoded) {
-                                       break;
-                               }
-                       }
-                       av_free(frame);
-
-                       avcodec_close(audio_stream->codec);
                }
                if (audio_stream->codec->channels > 0) {
                        set_value_int64 (metadata, "nfo:channels", audio_stream->codec->channels);
@@ -207,37 +177,6 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
                if (video_stream->codec->width > 0 && video_stream->codec->height > 0) {
                        set_value_int64 (metadata, "nfo:width", video_stream->codec->width);
                        set_value_int64 (metadata, "nfo:height", video_stream->codec->height);
-               } else if (avcodec_open2(video_stream->codec, video_codec, 0) >= 0) {
-                       AVFrame *frame;
-                       AVPacket packet;
-                       av_init_packet(&packet);
-
-                       frame = avcodec_alloc_frame();
-
-                       av_seek_frame(format, video_stream_index, -1, 0);
-                       for (;;) {
-                               int decoded = 0;
-                               if (av_read_frame(format, &packet) < 0) {
-                                       break;
-                               } else if (packet.stream_index != video_stream_index) {
-                               } else if (!avcodec_decode_video2(
-                                       video_stream->codec, frame, &decoded, &packet) < 0) {
-                                       av_free_packet(&packet);
-                                       break;
-                               } else if (video_stream->codec->width > 0 && video_stream->codec->height > 0) 
{
-                                       set_value_int64 (metadata, "nfo:width", video_stream->codec->width);
-                                       set_value_int64 (metadata, "nfo:height", video_stream->codec->height);
-                                       break;
-                               }
-                               av_free_packet(&packet);
-
-                               if (decoded) {
-                                       break;
-                               }
-                       }
-                       av_free(frame);
-
-                       avcodec_close(video_stream->codec);
                }
 
                if (video_stream->avg_frame_rate.num > 0) {