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I just purchased a cheap dashboard video-camera that is advertised to have a H.264 codec inside. However, after the first video test I have seen that a 43sec movie takes 123MB! How is this possible. I thought that H.264 has a MUCH better compression!

Question:
1. Does my video camera really incorporate a true H.264 codec or is it a fake?
2. If it is a true H264 why is the compression ratio so poor?


UPDATE:
I contacted the producer and they said that "The compression ratio system setting of the H.264 AVC codec is 102:1. This setting cannot be set manually"


000000 File Type (20 bytes)
000000  Header (8 bytes)
000000   Size:                                 20 (0x00000014)
000004   Name:                                 ftyp
000008  MajorBrand:                            qt  
00000C  MajorBrandVersion:                     512 (0x00000200)
000010  CompatibleBrand:                       qt  
000014 ----------------------------
000014 ---   MPEG-4, accepted   ---
000014 ----------------------------
000014 Data (3774264 bytes)
000014  Header (8 bytes)
000014   Size:                                 3774264 (0x00399738)
000018   Name:                                 mdat
00001C  Data:                                  (3774256 bytes)
39974C File header (2128 bytes)
39974C  Header (8 bytes)
39974C   Size:                                 2128 (0x00000850)
399750   Name:                                 moov
399754  Movie header (108 bytes)
399754   Header (8 bytes)
399754    Size:                                108 (0x0000006C)
399758    Name:                                mvhd
39975C   Version:                              0 (0x00)
39975D   Flags:                                0 (0x000000)
399760   Creation time:                        3118707150 (0xB9E3B1CE)
399764   Modification time:                    3118707150 (0xB9E3B1CE)
399768   Time scale:                           1000 (0x000003E8)
39976C   Duration:                             2221 (0x000008AD)
399770   Preferred rate:                       65536 (0x00010000)
399774   Preferred volume:                     256 (0x0100)
399776   Reserved:                             (10 bytes)
399780   Matrix structure (36 bytes)
399780    a (width scale):                     1.000
399784    b (width rotate):                    0.000
399788    u (width angle):                     0.000
39978C    c (height rotate):                   0.000
399790    d (height scale):                    1.000
399794    v (height angle):                    0.000
399798    x (position left):                   0.000
39979C    y (position top):                    0.000
3997A0    w (divider):                         1.000
3997A4   Preview time:                         0 (0x00000000)
3997A8   Preview duration:                     0 (0x00000000)
3997AC   Poster time:                          0 (0x00000000)
3997B0   Selection time:                       0 (0x00000000)
3997B4   Selection duration:                   0 (0x00000000)
3997B8   Current time:                         0 (0x00000000)
3997BC   Next track ID:                        3 (0x00000003)
3997C0  Track (1547 bytes)
3997C0   Header (8 bytes)
3997C0    Size:                                1547 (0x0000060B)
3997C4    Name:                                trak
3997C8   Track Header (92 bytes)
3997C8    Header (8 bytes)
3997C8     Size:                               92 (0x0000005C)
3997CC     Name:                               tkhd
3997D0    Version:                             0 (0x00)
3997D1    Flags:                               15 (0x00000F)
3997D4    Track Enabled:                       Yes
3997D4    Track in Movie:                      2 (0x0000000000000002)
3997D4    Track in Preview:                    4 (0x0000000000000004)
3997D4    Track in Poster:                     8 (0x0000000000000008)
3997D4    Creation time:                       3118707150 (0xB9E3B1CE)
3997D8    Modification time:                   3118707150 (0xB9E3B1CE)
3997DC    Track ID:                            1 (0x00000001)
3997E0    Reserved:                            0 (0x00000000)
3997E4    Duration:                            2221 (0x000008AD)
3997E8    Reserved:                            0 (0x00000000)
3997EC    Reserved:                            0 (0x00000000)
3997F0    Layer:                               0 (0x0000)
3997F2    Alternate group:                     0 (0x0000)
3997F4    Volume:                              0 (0x0000)
3997F6    Reserved:                            0 (0x0000)
3997F8    Matrix structure (36 bytes)
3997F8     a (width scale):                    1.000
3997FC     b (width rotate):                   0.000
399800     u (width angle):                    0.000
399804     c (height rotate):                  0.000
399808     d (height scale):                   1.000
39980C     v (height angle):                   0.000
399810     x (position left):                  0.000
399814     y (position top):                   0.000
399818     w (divider):                        1.000
39981C    Track width:                         1920.000
399820    Track height:                        1080.000
399824   Media (1447 bytes)
399824    Header (8 bytes)
399824     Size:                               1447 (0x000005A7)
399828     Name:                               mdia
39982C    Media Header (32 bytes)
39982C     Header (8 bytes)
39982C      Size:                              32 (0x00000020)
399830      Name:                              mdhd
399834     Version:                            0 (0x00)
399835     Flags:                              0 (0x000000)
399838     Creation time:                      3118707150 (0xB9E3B1CE)
39983C     Modification time:                  3118707150 (0xB9E3B1CE)
399840     Time scale:                         1000 (0x000003E8)
399844     Duration:                           2221 (0x000008AD)
399848     Language:                           0 (0x0000)
39984A     Quality:                            0 (0x0000)
39984C    Handler Reference (45 bytes)
39984C     Header (8 bytes)
39984C      Size:                              45 (0x0000002D)
399850      Name:                              hdlr
399854     Version:                            0 (0x00)
399855     Flags:                              0 (0x000000)
399858     Component type:                     mhlr
39985C     Component subtype:                  vide
399860     Component manufacturer:             
399864     Component flags:                    0 (0x00000000)
399868     Component flags mask:               0 (0x00000000)
39986C     Component name size:                12 (0x0C)
39986D     Component name:                     VideoHandler
399879    Media Information (1362 bytes)
399879     Header (8 bytes)
399879      Size:                              1362 (0x00000552)
39987D      Name:                              minf
399881     Video Media Header (20 bytes)
399881      Header (8 bytes)
399881       Size:                             20 (0x00000014)

    ................
25E131   ------------------------
25E131   ---   AVC, filling   ---
25E131   ------------------------
25E131   slice_data (21876 bytes)
25E131    (ToDo):                              (Data)
2636A8   --------------------------------------------
2636A8   ---   MPEG-4, jumping to offset 3004D4   ---
2636A8   --------------------------------------------
3004D4  2 (64000 bytes)
3004D4   Channel grouping data:                (64000 bytes)
3004D4   Block (64000 bytes)
3004D4    Data:                                (64000 bytes)
30FED4   -------------------------
30FED4   ---   PCM, accepted   ---
30FED4   -------------------------
30FED4   ------------------------
30FED4   ---   PCM, filling   ---
30FED4   ------------------------
30FED4   --------------------------------------------
30FED4   ---   MPEG-4, jumping to offset 399FCB   ---
30FED4   --------------------------------------------
3204D4 ---------------------------
3204D4 ---   MPEG-4, filling   ---
3204D4 ---------------------------
3204D4 ----------------------------
3204D4 ---   MPEG-4, finished   ---
3204D4 ----------------------------
1

H264 allows for much better compression, but image acquisition should be as good as feasible, so cameras will capture at a high bitrate, say, 10+ Mbps, depends on resolution and framerate. Nothing unusual about that.

The full bouquet of H.264 compression methods i.e. lookahead for rate-control, better motion estimation ..etc is usually applied when producing a file for web playback. You can use ffmpeg with libx264 to achieve that.

  • Ok. But I had before a cam with mp2 compression. The file size was IDENTICAL. So, there must be something wrong about this camera if its mp4 compressor produces same results as the old camera. – Rigel Jul 21 '18 at 8:46
  • Camera compressors aren't trying to squeeze out small files. They have a set of fixed target profiles. Check the camera menu and manual for lower bitrates. – Gyan Jul 21 '18 at 10:16
  • @gyan-this is a cheap dashboard camera advertised as h264. there are no settings related to video! – Rigel Jul 21 '18 at 10:18
  • Then you'll have to recompress after recording. – Gyan Jul 21 '18 at 10:19
  • My problem is that this camera will kill the SD card after a few months only because of the intense writing. I replaced my old mp2 camera with this one hoping to get less I/O activity. – Rigel Jul 21 '18 at 10:22

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