想问个关于XviD帧大小的问题

[nonocast]

<>之前都是XviD自己TRACE出来的
<>中是我在程序TRACE出来每一帧的数据大小
为什么两个length 差距会这么大
有人知道吗？
还有就是大小为6的帧是什么意思，我忽略好像也照样能放


[ 0] type=I Q: 4 length: 2761 <2761>

[ 1] type=B Q: 6 length: 27 <1674>
[ 2] type=P Q: 3 length: 1653 <6>
[ 3] type=B Q: 6 length: 48 <624>
[ 4] type=P Q: 4 length: 582 <6>
[ 5] type=B Q: 6 length: 26 <999>
[ 6] type=P Q: 3 length: 979 <6>
[ 7] type=B Q: 5 length: 235 <1898>
[ 8] type=P Q: 3 length: 1669 <6>
[ 9] type=P Q: 2 length: 3583 <3583>
[ 10] type=P Q: 3 length: 2331 <2331>
[ 11] type=B Q: 5 length: 731 <2467>
[ 12] type=P Q: 3 length: 1742 <6>

[ 13] type=B Q: 5 length: 674 <3032>
[ 14] type=B Q: 5 length: 362 <362>
[ 15] type=P Q: 3 length: 2364 <6>
[ 16] type=B Q: 4 length: 632 <4361>
[ 17] type=B Q: 4 length: 806 <806>
[ 18] type=P Q: 2 length: 3735 <6>
[ 19] type=B Q: 4 length: 485 <2499>
[ 20] type=P Q: 3 length: 2020 <6>
[ 21] type=B Q: 4 length: 386 <3480>
[ 22] type=B Q: 4 length: 657 <657>
[ 23] type=P Q: 2 length: 3100 <6>
[ 24] type=B Q: 4 length: 551 <2654>
[ 25] type=P Q: 3 length: 2109 <6>
[ 26] type=B Q: 4 length: 893 <4377>
[ 27] type=P Q: 2 length: 3490 <6>
[ 28] type=P Q: 2 length: 3434 <3434>
[ 29] type=P Q: 2 length: 3244 <3244>
[ 30] type=P Q: 3 length: 1814 <1814>
[ 31] type=B Q: 4 length: 654 <4184>
[ 32] type=P Q: 2 length: 3536 <6>
[ 33] type=B Q: 4 length: 937 <5589>
[ 34] type=P Q: 2 length: 4658 <6>
[ 35] type=B Q: 4 length: 436 <3929>
[ 36] type=P Q: 2 length: 3499 <6>
[ 37] type=B Q: 4 length: 346 <2142>
[ 38] type=P Q: 3 length: 1802 <6>
[ 39] type=B Q: 4 length: 160 <2910>
[ 40] type=P Q: 2 length: 2756 <6>
[ 41] type=B Q: 4 length: 71 <1582>
[ 42] type=P Q: 2 length: 1517 <6>
[ 43] type=B Q: 4 length: 88 <1538>
[ 44] type=P Q: 2 length: 1456 <6>
[ 45] type=B Q: 3 length: 109 <5855>
[ 46] type=P Q: 1 length: 5752 <6>
[ 47] type=B Q: 3 length: 59 <667>
[ 48] type=P Q: 2 length: 614 <6>
[ 49] type=B Q: 4 length: 45 <1585>
[ 50] type=P Q: 2 length: 1546 <6>
[ 51] type=B Q: 4 length: 76 <2032>
[ 52] type=P Q: 2 length: 1962 <6>
[ 53] type=B Q: 4 length: 83 <3189>
[ 54] type=P Q: 2 length: 3112 <6>
[ 55] type=B Q: 4 length: 80 <2293>
[ 56] type=P Q: 2 length: 2219 <6>
[ 57] type=B Q: 3 length: 133 <5883>
[ 58] type=P Q: 1 length: 5756 <6>
[ 59] type=B Q: 3 length: 81 <849>
[ 60] type=P Q: 2 length: 774 <6>
[ 61] type=B Q: 4 length: 51 <1149>
[ 62] type=P Q: 2 length: 1104 <6>
[ 63] type=B Q: 4 length: 56 <1491>
[ 64] type=P Q: 2 length: 1441 <6>
[ 65] type=B Q: 3 length: 62 <5500>
[ 66] type=P Q: 1 length: 5444 <6>
[ 67] type=B Q: 3 length: 67 <1044>
[ 68] type=P Q: 2 length: 983 <6>
[ 69] type=B Q: 3 length: 131 <7145>
[ 70] type=P Q: 1 length: 7020 <6>
[ 71] type=B Q: 3 length: 1213 <5507>
[ 72] type=P Q: 2 length: 4300 <6>
[ 73] type=P Q: 2 length: 4001 <4001>
[ 74] type=P Q: 1 length: 9591 <9591>
[ 75] type=B Q: 3 length: 1405 <5495>
[ 76] type=P Q: 2 length: 4096 <6>
[ 77] type=B Q: 3 length: 946 <11086>
[ 78] type=P Q: 1 length: 10146 <6>
[ 79] type=B Q: 3 length: 951 <4151>
[ 80] type=P Q: 2 length: 3206 <6>
[ 81] type=B Q: 4 length: 432 <3804>
[ 82] type=P Q: 2 length: 3378 <6>
[ 83] type=B Q: 3 length: 317 <8332>
[ 84] type=P Q: 1 length: 8021 <6>
[ 85] type=B Q: 3 length: 103 <1136>
[ 86] type=B Q: 3 length: 67 <67>
[ 87] type=P Q: 2 length: 1039 <6>
[ 88] type=B Q: 3 length: 107 <5761>
[ 89] type=B Q: 3 length: 96 <96>
[ 90] type=P Q: 1 length: 5660 <6>
[ 91] type=B Q: 3 length: 71 <861>
[ 92] type=B Q: 3 length: 80 <80>
[ 93] type=P Q: 2 length: 796 <6>
[ 94] type=B Q: 3 length: 60 <5205>
[ 95] type=B Q: 3 length: 52 <52>
[ 96] type=P Q: 1 length: 5151 <6>
[ 97] type=B Q: 3 length: 80 <1006>
[ 98] type=B Q: 3 length: 185 <185>
[ 99] type=P Q: 2 length: 932 <6>
[ 100] type=B Q: 3 length: 68 <5426>
[ 101] type=B Q: 3 length: 74 <74>
[ 102] type=P Q: 1 length: 5364 <6>
[ 103] type=B Q: 3 length: 65 <778>
[ 104] type=B Q: 3 length: 83 <83>
[ 105] type=P Q: 2 length: 719 <6>
[ 106] type=B Q: 3 length: 66 <5254>
[ 107] type=B Q: 3 length: 58 <58>
[ 108] type=P Q: 1 length: 5194 <6>
[ 109] type=B Q: 3 length: 78 <986>
[ 110] type=B Q: 3 length: 88 <88>
[ 111] type=P Q: 2 length: 914 <6>
[ 112] type=B Q: 3 length: 1066 <10444>
[ 113] type=P Q: 1 length: 9384 <6>
[ 114] type=B Q: 2 length: 2947 <13805>
[ 115] type=P Q: 1 length: 10864 <6>
[ 116] type=P Q: 2 length: 3493 <3493>
[ 117] type=B Q: 3 length: 1093 <10331>
[ 118] type=P Q: 1 length: 9244 <6>
[ 119] type=B Q: 2 length: 1499 <9311>
[ 120] type=P Q: 1 length: 7818 <6>
[ 121] type=B Q: 3 length: 226 <2372>
[ 122] type=P Q: 2 length: 2152 <6>
[ 123] type=B Q: 3 length: 53 <7081>

[yyhzpk]

不懂

[adamchao]

因为帧的类型不同，所以大小也不同。TYPE 为I 的帧是关键帧，一般情况下是比较大的
TYPE 为 P 和 B 的帧是非关键帧，相对来说比较小，一般情况下 P 帧比 B 帧 要大些。