/* GStreamer * Copyright (C) 2007 Jan Schmidt * Copyright (C) 2009 Carl-Anton Ingmarsson * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #include #include #include "mpegutil.h" /* default intra quant matrix, in zig-zag order */ static const guint8 default_intra_quantizer_matrix[64] = { 8, 16, 16, 19, 16, 19, 22, 22, 22, 22, 22, 22, 26, 24, 26, 27, 27, 27, 26, 26, 26, 26, 27, 27, 27, 29, 29, 29, 34, 34, 34, 29, 29, 29, 27, 27, 29, 29, 32, 32, 34, 34, 37, 38, 37, 35, 35, 34, 35, 38, 38, 40, 40, 40, 48, 48, 46, 46, 56, 56, 58, 69, 69, 83 }; guint8 mpeg2_scan[64] = { /* Zig-Zag scan pattern */ 0, 1, 8, 16, 9, 2, 3, 10, 17, 24, 32, 25, 18, 11, 4, 5, 12, 19, 26, 33, 40, 48, 41, 34, 27, 20, 13, 6, 7, 14, 21, 28, 35, 42, 49, 56, 57, 50, 43, 36, 29, 22, 15, 23, 30, 37, 44, 51, 58, 59, 52, 45, 38, 31, 39, 46, 53, 60, 61, 54, 47, 55, 62, 63 }; static void set_fps_from_code (MPEGSeqHdr * hdr, guint8 fps_code) { const gint framerates[][2] = { {30, 1}, {24000, 1001}, {24, 1}, {25, 1}, {30000, 1001}, {30, 1}, {50, 1}, {60000, 1001}, {60, 1}, {30, 1} }; if (fps_code < 10) { hdr->fps_n = framerates[fps_code][0]; hdr->fps_d = framerates[fps_code][1]; } else { /* Force a valid framerate */ hdr->fps_n = 30000; hdr->fps_d = 1001; } } /* Set the Pixel Aspect Ratio in our hdr from a DAR code in the data */ static void set_par_from_dar (MPEGSeqHdr * hdr, guint8 asr_code) { /* Pixel_width = DAR_width * display_vertical_size */ /* Pixel_height = DAR_height * display_horizontal_size */ switch (asr_code) { case 0x02: /* 3:4 DAR = 4:3 pixels */ hdr->par_w = 4 * hdr->height; hdr->par_h = 3 * hdr->width; break; case 0x03: /* 9:16 DAR */ hdr->par_w = 16 * hdr->height; hdr->par_h = 9 * hdr->width; break; case 0x04: /* 1:2.21 DAR */ hdr->par_w = 221 * hdr->height; hdr->par_h = 100 * hdr->width; break; case 0x01: /* Square pixels */ default: hdr->par_w = hdr->par_h = 1; break; } } gboolean mpeg_util_parse_sequence_extension (MPEGSeqExtHdr * hdr, GstBuffer * buffer) { GstBitReader reader = GST_BIT_READER_INIT_FROM_BUFFER (buffer);; /* skip sync word */ if (!gst_bit_reader_skip (&reader, 8 * 4)) return FALSE; /* skip extension code */ if (!gst_bit_reader_skip (&reader, 4)) return FALSE; /* skip profile and level escape bit */ if (!gst_bit_reader_skip (&reader, 1)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->profile, 3)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->level, 4)) return FALSE; /* progressive */ if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->progressive, 1)) return FALSE; /* chroma format */ if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->chroma_format, 2)) return FALSE; /* resolution extension */ if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->horiz_size_ext, 2)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->vert_size_ext, 2)) return FALSE; if (!gst_bit_reader_get_bits_uint16 (&reader, &hdr->bitrate_ext, 12)) return FALSE; /* skip to framerate extension */ if (!gst_bit_reader_skip (&reader, 9)) return FALSE; /* framerate extension */ if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->fps_n_ext, 2)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->fps_d_ext, 2)) return FALSE; return TRUE; } gboolean mpeg_util_parse_sequence_hdr (MPEGSeqHdr * hdr, GstBuffer * buffer) { GstBitReader reader = GST_BIT_READER_INIT_FROM_BUFFER (buffer); guint8 dar_idx, par_idx; guint8 load_intra_flag, load_non_intra_flag; /* skip sync word */ if (!gst_bit_reader_skip (&reader, 8 * 4)) return FALSE; /* resolution */ if (!gst_bit_reader_get_bits_uint16 (&reader, &hdr->width, 12)) return FALSE; if (!gst_bit_reader_get_bits_uint16 (&reader, &hdr->height, 12)) return FALSE; /* aspect ratio */ if (!gst_bit_reader_get_bits_uint8 (&reader, &dar_idx, 4)) return FALSE; set_par_from_dar (hdr, dar_idx); /* framerate */ if (!gst_bit_reader_get_bits_uint8 (&reader, &par_idx, 4)) return FALSE; set_fps_from_code (hdr, par_idx); /* bitrate */ if (!gst_bit_reader_get_bits_uint32 (&reader, &hdr->bitrate, 18)) return FALSE; if (!gst_bit_reader_skip (&reader, 1)) return FALSE; /* VBV buffer size */ if (!gst_bit_reader_get_bits_uint16 (&reader, &hdr->vbv_buffer, 10)) return FALSE; /* constrained parameters flag */ if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->constrained_parameters_flag, 1)) return FALSE; /* intra quantizer matrix */ if (!gst_bit_reader_get_bits_uint8 (&reader, &load_intra_flag, 1)) return FALSE; if (load_intra_flag) { gint i; for (i = 0; i < 64; i++) { if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->intra_quantizer_matrix[mpeg2_scan[i]], 8)) return FALSE; } } else memcpy (hdr->intra_quantizer_matrix, default_intra_quantizer_matrix, 64); /* non intra quantizer matrix */ if (!gst_bit_reader_get_bits_uint8 (&reader, &load_non_intra_flag, 1)) return FALSE; if (load_non_intra_flag) { gint i; for (i = 0; i < 64; i++) { if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->non_intra_quantizer_matrix[mpeg2_scan[i]], 8)) return FALSE; } } else memset (hdr->non_intra_quantizer_matrix, 16, 64); return TRUE; } gboolean mpeg_util_parse_picture_hdr (MPEGPictureHdr * hdr, GstBuffer * buffer) { GstBitReader reader = GST_BIT_READER_INIT_FROM_BUFFER (buffer); /* skip sync word */ if (!gst_bit_reader_skip (&reader, 8 * 4)) return FALSE; /* temperal sequence number */ if (!gst_bit_reader_get_bits_uint16 (&reader, &hdr->tsn, 10)) return FALSE; /* frame type */ if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->pic_type, 3)) return FALSE; if (hdr->pic_type == 0 || hdr->pic_type > 4) return FALSE; /* Corrupted picture packet */ /* VBV delay */ if (!gst_bit_reader_get_bits_uint16 (&reader, &hdr->vbv_delay, 16)) return FALSE; if (hdr->pic_type == P_FRAME || hdr->pic_type == B_FRAME) { if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->full_pel_forward_vector, 1)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->f_code[0][0], 3)) return FALSE; hdr->f_code[0][1] = hdr->f_code[0][0]; } else { hdr->full_pel_forward_vector = 0; hdr->f_code[0][0] = hdr->f_code[0][1] = 0; } if (hdr->pic_type == B_FRAME) { if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->full_pel_backward_vector, 1)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &hdr->f_code[1][0], 3)) return FALSE; hdr->f_code[1][1] = hdr->f_code[1][0]; } else { hdr->full_pel_backward_vector = 0; hdr->f_code[1][0] = hdr->f_code[1][1] = 0; } return TRUE; } gboolean mpeg_util_parse_picture_coding_extension (MPEGPictureExt * ext, GstBuffer * buffer) { GstBitReader reader = GST_BIT_READER_INIT_FROM_BUFFER (buffer); /* skip sync word */ if (!gst_bit_reader_skip (&reader, 8 * 4)) return FALSE; /* skip extension code */ if (!gst_bit_reader_skip (&reader, 4)) return FALSE; /* f_code */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->f_code[0][0], 4)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->f_code[0][1], 4)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->f_code[1][0], 4)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->f_code[1][1], 4)) return FALSE; /* intra DC precision */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->intra_dc_precision, 2)) return FALSE; /* picture structure */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->picture_structure, 2)) return FALSE; /* top field first */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->top_field_first, 1)) return FALSE; /* frame pred frame dct */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->frame_pred_frame_dct, 1)) return FALSE; /* concealment motion vectors */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->concealment_motion_vectors, 1)) return FALSE; /* q scale type */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->q_scale_type, 1)) return FALSE; /* intra vlc format */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->intra_vlc_format, 1)) return FALSE; /* alternate scan */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->alternate_scan, 1)) return FALSE; /* repeat first field */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->repeat_first_field, 1)) return FALSE; /* chroma_420_type */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->chroma_420_type, 1)) return FALSE; /* progressive_frame */ if (!gst_bit_reader_get_bits_uint8 (&reader, &ext->progressive_frame, 1)) return FALSE; return TRUE; } gboolean mpeg_util_parse_gop (MPEGGop * gop, GstBuffer * buffer) { GstBitReader reader = GST_BIT_READER_INIT_FROM_BUFFER (buffer); /* skip sync word */ if (!gst_bit_reader_skip (&reader, 8 * 4)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &gop->drop_frame_flag, 1)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &gop->hour, 5)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &gop->minute, 6)) return FALSE; /* skip unused bit */ if (!gst_bit_reader_skip (&reader, 1)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &gop->second, 6)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &gop->frame, 6)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &gop->closed_gop, 1)) return FALSE; if (!gst_bit_reader_get_bits_uint8 (&reader, &gop->broken_gop, 1)) return FALSE; return TRUE; } gboolean mpeg_util_parse_quant_matrix (MPEGQuantMatrix * qm, GstBuffer * buffer) { GstBitReader reader = GST_BIT_READER_INIT_FROM_BUFFER (buffer); guint8 load_intra_flag, load_non_intra_flag; /* skip sync word */ if (!gst_bit_reader_skip (&reader, 8 * 4)) return FALSE; /* skip extension code */ if (!gst_bit_reader_skip (&reader, 4)) return FALSE; /* intra quantizer matrix */ if (!gst_bit_reader_get_bits_uint8 (&reader, &load_intra_flag, 1)) return FALSE; if (load_intra_flag) { gint i; for (i = 0; i < 64; i++) { if (!gst_bit_reader_get_bits_uint8 (&reader, &qm->intra_quantizer_matrix[mpeg2_scan[i]], 8)) return FALSE; } } else memcpy (qm->intra_quantizer_matrix, default_intra_quantizer_matrix, 64); /* non intra quantizer matrix */ if (!gst_bit_reader_get_bits_uint8 (&reader, &load_non_intra_flag, 1)) return FALSE; if (load_non_intra_flag) { gint i; for (i = 0; i < 64; i++) { if (!gst_bit_reader_get_bits_uint8 (&reader, &qm->non_intra_quantizer_matrix[mpeg2_scan[i]], 8)) return FALSE; } } else memset (qm->non_intra_quantizer_matrix, 16, 64); return TRUE; }