/* * MPEG-4 decoder / encoder common code * Copyright (c) 2000,2001 Fabrice Bellard * Copyright (c) 2002-2010 Michael Niedermayer * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "mpegutils.h" #include "mpegvideo.h" #include "mpeg4video.h" #include "mpeg4data.h" int ff_mpeg4_get_video_packet_prefix_length(enum AVPictureType pict_type, int f_code, int b_code) { switch (pict_type) { case AV_PICTURE_TYPE_I: return 16; case AV_PICTURE_TYPE_P: case AV_PICTURE_TYPE_S: return f_code + 15; case AV_PICTURE_TYPE_B: return FFMAX3(f_code, b_code, 2) + 15; default: return -1; } } void ff_mpeg4_clean_buffers(MpegEncContext *s) { const int mb_height = s->mb_height; int c_wrap, l_wrap, l_xy; l_wrap = s->b8_stride; l_xy = (2 * s->mb_y - 1) * l_wrap + s->mb_x * 2 - 1; c_wrap = s->mb_stride; int u_xy = 2 * mb_height * l_wrap + s->mb_y * c_wrap + s->mb_x - 1; int v_xy = u_xy + c_wrap * (mb_height + 1); int16_t (*ac_val)[16] = s->ac_val; /* clean AC */ memset(ac_val + l_xy, 0, (l_wrap * 2 + 1) * sizeof(*ac_val)); memset(ac_val + u_xy, 0, (c_wrap + 1) * sizeof(*ac_val)); memset(ac_val + v_xy, 0, (c_wrap + 1) * sizeof(*ac_val)); /* clean MV */ // we can't clear the MVs as they might be needed by a B-frame s->last_mv[0][0][0] = s->last_mv[0][0][1] = s->last_mv[1][0][0] = s->last_mv[1][0][1] = 0; } #define tab_size ((signed)FF_ARRAY_ELEMS(s->direct_scale_mv[0])) #define tab_bias (tab_size / 2) // used by MPEG-4 and rv10 decoder void ff_mpeg4_init_direct_mv(MpegEncContext *s) { int i; for (i = 0; i < tab_size; i++) { s->direct_scale_mv[0][i] = (i - tab_bias) * s->pb_time / s->pp_time; s->direct_scale_mv[1][i] = (i - tab_bias) * (s->pb_time - s->pp_time) / s->pp_time; } } static inline void ff_mpeg4_set_one_direct_mv(MpegEncContext *s, int mx, int my, int i) { int xy = s->block_index[i]; uint16_t time_pp = s->pp_time; uint16_t time_pb = s->pb_time; int p_mx, p_my; p_mx = s->next_pic.motion_val[0][xy][0]; if ((unsigned)(p_mx + tab_bias) < tab_size) { s->mv[0][i][0] = s->direct_scale_mv[0][p_mx + tab_bias] + mx; s->mv[1][i][0] = mx ? s->mv[0][i][0] - p_mx : s->direct_scale_mv[1][p_mx + tab_bias]; } else { s->mv[0][i][0] = p_mx * time_pb / time_pp + mx; s->mv[1][i][0] = mx ? s->mv[0][i][0] - p_mx : p_mx * (time_pb - time_pp) / time_pp; } p_my = s->next_pic.motion_val[0][xy][1]; if ((unsigned)(p_my + tab_bias) < tab_size) { s->mv[0][i][1] = s->direct_scale_mv[0][p_my + tab_bias] + my; s->mv[1][i][1] = my ? s->mv[0][i][1] - p_my : s->direct_scale_mv[1][p_my + tab_bias]; } else { s->mv[0][i][1] = p_my * time_pb / time_pp + my; s->mv[1][i][1] = my ? s->mv[0][i][1] - p_my : p_my * (time_pb - time_pp) / time_pp; } } #undef tab_size #undef tab_bias /** * @return the mb_type */ int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my) { const int mb_index = s->mb_x + s->mb_y * s->mb_stride; const int colocated_mb_type = s->next_pic.mb_type[mb_index]; uint16_t time_pp; uint16_t time_pb; int i; // FIXME avoid divides // try special case with shifts for 1 and 3 B-frames? if (IS_8X8(colocated_mb_type)) { s->mv_type = MV_TYPE_8X8; for (i = 0; i < 4; i++) ff_mpeg4_set_one_direct_mv(s, mx, my, i); return MB_TYPE_DIRECT2 | MB_TYPE_8x8 | MB_TYPE_BIDIR_MV; } else if (IS_INTERLACED(colocated_mb_type)) { s->mv_type = MV_TYPE_FIELD; for (i = 0; i < 2; i++) { int field_select = s->next_pic.ref_index[0][4 * mb_index + 2 * i]; s->field_select[0][i] = field_select; s->field_select[1][i] = i; if (s->top_field_first) { time_pp = s->pp_field_time - field_select + i; time_pb = s->pb_field_time - field_select + i; } else { time_pp = s->pp_field_time + field_select - i; time_pb = s->pb_field_time + field_select - i; } s->mv[0][i][0] = s->p_field_mv_table[i][0][mb_index][0] * time_pb / time_pp + mx; s->mv[0][i][1] = s->p_field_mv_table[i][0][mb_index][1] * time_pb / time_pp + my; s->mv[1][i][0] = mx ? s->mv[0][i][0] - s->p_field_mv_table[i][0][mb_index][0] : s->p_field_mv_table[i][0][mb_index][0] * (time_pb - time_pp) / time_pp; s->mv[1][i][1] = my ? s->mv[0][i][1] - s->p_field_mv_table[i][0][mb_index][1] : s->p_field_mv_table[i][0][mb_index][1] * (time_pb - time_pp) / time_pp; } return MB_TYPE_DIRECT2 | MB_TYPE_16x8 | MB_TYPE_BIDIR_MV | MB_TYPE_INTERLACED; } else { ff_mpeg4_set_one_direct_mv(s, mx, my, 0); s->mv[0][1][0] = s->mv[0][2][0] = s->mv[0][3][0] = s->mv[0][0][0]; s->mv[0][1][1] = s->mv[0][2][1] = s->mv[0][3][1] = s->mv[0][0][1]; s->mv[1][1][0] = s->mv[1][2][0] = s->mv[1][3][0] = s->mv[1][0][0]; s->mv[1][1][1] = s->mv[1][2][1] = s->mv[1][3][1] = s->mv[1][0][1]; if ((s->avctx->workaround_bugs & FF_BUG_DIRECT_BLOCKSIZE) || !s->quarter_sample) s->mv_type = MV_TYPE_16X16; else s->mv_type = MV_TYPE_8X8; // Note see prev line return MB_TYPE_DIRECT2 | MB_TYPE_16x16 | MB_TYPE_BIDIR_MV; } }