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Diffstat (limited to 'src/video_dec/libmpeg2/header.c')
-rw-r--r-- | src/video_dec/libmpeg2/header.c | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/src/video_dec/libmpeg2/header.c b/src/video_dec/libmpeg2/header.c new file mode 100644 index 000000000..0c2b76891 --- /dev/null +++ b/src/video_dec/libmpeg2/header.c @@ -0,0 +1,419 @@ +/* + * header.c + * Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org> + * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca> + * + * This file is part of mpeg2dec, a free MPEG-2 video stream decoder. + * See http://libmpeg2.sourceforge.net/ for updates. + * + * mpeg2dec is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * mpeg2dec 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* +#define LOG_PAN_SCAN +*/ + +#include "config.h" + +#include <stdio.h> /* For printf debugging */ +#include <inttypes.h> + +#include "mpeg2_internal.h" +#include <xine/attributes.h> + +/* default intra quant matrix, in zig-zag order */ +static const uint8_t default_intra_quantizer_matrix[64] ATTR_ALIGN(16) = { + 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 +}; + +uint8_t mpeg2_scan_norm[64] ATTR_ALIGN(16) = +{ + /* 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 +}; + +uint8_t mpeg2_scan_alt[64] ATTR_ALIGN(16) = +{ + /* Alternate scan pattern */ + 0,8,16,24,1,9,2,10,17,25,32,40,48,56,57,49, + 41,33,26,18,3,11,4,12,19,27,34,42,50,58,35,43, + 51,59,20,28,5,13,6,14,21,29,36,44,52,60,37,45, + 53,61,22,30,7,15,23,31,38,46,54,62,39,47,55,63 +}; + +/* count must be between 1 and 32 */ +static uint32_t get_bits(uint8_t *buffer, uint32_t count, uint32_t *bit_position) { + uint32_t byte_offset; + uint32_t bit_offset; + uint32_t bit_mask; + uint32_t bit_bite; + uint32_t result=0; + if (count == 0) return 0; + do { + byte_offset = *bit_position >> 3; /* Div 8 */ + bit_offset = 8 - (*bit_position & 0x7); /* Bits got 87654321 */ + bit_mask = ((1 << (bit_offset)) - 1); + bit_bite = bit_offset; + if (count < bit_offset) { + bit_mask ^= ((1 << (bit_offset-count)) - 1); + bit_bite = count; + } + /* + printf("Byte=0x%02x Bitmask=0x%04x byte_offset=%u bit_offset=%u bit_byte=%u count=%u\n",buffer[byte_offset], bit_mask, byte_offset, bit_offset, bit_bite,count); + */ + result = (result << bit_bite) | ((buffer[byte_offset] & bit_mask) >> (bit_offset-bit_bite)); + *bit_position+=bit_bite; + count-=bit_bite; + } while ((count > 0) && (byte_offset<50) ); + return result; +} + +static int32_t get_bits_signed(uint8_t *buffer, uint32_t count, uint32_t *bit_position) { + uint32_t value = get_bits(buffer, count, bit_position); + uint32_t sign_mask = (uint32_t)(-1 << (count - 1)); + if (value & sign_mask) + value |= sign_mask; /* sign-extend value */ + return (int32_t)value; +} + +void mpeg2_header_state_init (picture_t * picture) +{ + picture->scan = mpeg2_scan_norm; + picture->load_intra_quantizer_matrix = 1; + picture->load_non_intra_quantizer_matrix = 1; +} + +int mpeg2_header_sequence (picture_t * picture, uint8_t * buffer) +{ + int width, height; + int i; + + if ((buffer[6] & 0x20) != 0x20) + return 1; /* missing marker_bit */ + + height = (buffer[0] << 16) | (buffer[1] << 8) | buffer[2]; + + picture->display_width = width = (height >> 12); + picture->display_height = height = (height & 0xfff); + + width = (width + 15) & ~15; + height = (height + 15) & ~15; + + if ((width > 1920) || (height > 1152)) + return 1; /* size restrictions for MP@HL */ + + picture->coded_picture_width = width; + picture->coded_picture_height = height; + + /* this is not used by the decoder */ + picture->aspect_ratio_information = buffer[3] >> 4; + picture->frame_rate_code = buffer[3] & 15; + picture->bitrate = (buffer[4]<<10)|(buffer[5]<<2)|(buffer[6]>>6); + + if (buffer[7] & 2) { + for (i = 0; i < 64; i++) + picture->intra_quantizer_matrix[mpeg2_scan_norm[i]] = + (buffer[i+7] << 7) | (buffer[i+8] >> 1); + buffer += 64; + } else + for (i = 0; i < 64; i++) + picture->intra_quantizer_matrix[mpeg2_scan_norm[i]] = + default_intra_quantizer_matrix [i]; + + if (buffer[7] & 1) + for (i = 0; i < 64; i++) + picture->non_intra_quantizer_matrix[mpeg2_scan_norm[i]] = + buffer[i+8]; + else + for (i = 0; i < 64; i++) + picture->non_intra_quantizer_matrix[i] = 16; + picture->load_intra_quantizer_matrix = 1; + picture->load_non_intra_quantizer_matrix = 1; + /* MPEG1 - for testing only */ + picture->mpeg1 = 1; + picture->intra_dc_precision = 0; + picture->frame_pred_frame_dct = 1; + picture->q_scale_type = 0; + picture->concealment_motion_vectors = 0; + /* picture->alternate_scan = 0; */ + picture->picture_structure = FRAME_PICTURE; + /* picture->second_field = 0; */ + + return 0; +} + +static int sequence_extension (picture_t * picture, uint8_t * buffer) +{ + /* check chroma format, size extensions, marker bit */ + if (((buffer[1] & 0x07) != 0x02) || (buffer[2] & 0xe0) || + ((buffer[3] & 0x01) != 0x01)) + return 1; + + /* this is not used by the decoder */ + picture->progressive_sequence = (buffer[1] >> 3) & 1; + + picture->low_delay = buffer[5] & 0x80; + + if (!picture->progressive_sequence) + picture->coded_picture_height = + (picture->coded_picture_height + 31) & ~31; + + + /* printf ("libmpeg2: low_delay : %d\n", picture->low_delay); */ + +/* + printf ("libmpeg2: sequence extension+5 : %08x (%d)\n", + buffer[5], buffer[5] % 0x80); + */ + + picture->frame_rate_ext_n = buffer[5] & 0x31; + picture->frame_rate_ext_d = (buffer[5] >> 2) & 0x03; + + /* MPEG1 - for testing only */ + picture->mpeg1 = 0; + + return 0; +} + +static int quant_matrix_extension (picture_t * picture, uint8_t * buffer) +{ + int i; + + if (buffer[0] & 8) { + for (i = 0; i < 64; i++) + picture->intra_quantizer_matrix[mpeg2_scan_norm[i]] = + (buffer[i] << 5) | (buffer[i+1] >> 3); + buffer += 64; + } + + if (buffer[0] & 4) + for (i = 0; i < 64; i++) + picture->non_intra_quantizer_matrix[mpeg2_scan_norm[i]] = + (buffer[i] << 6) | (buffer[i+1] >> 2); + + return 0; +} + +static int picture_coding_extension (picture_t * picture, uint8_t * buffer) +{ + /* pre subtract 1 for use later in compute_motion_vector */ + picture->f_motion.f_code[0] = (buffer[0] & 15) - 1; + picture->f_motion.f_code[1] = (buffer[1] >> 4) - 1; + picture->b_motion.f_code[0] = (buffer[1] & 15) - 1; + picture->b_motion.f_code[1] = (buffer[2] >> 4) - 1; + + picture->intra_dc_precision = (buffer[2] >> 2) & 3; + picture->picture_structure = buffer[2] & 3; + picture->frame_pred_frame_dct = (buffer[3] >> 6) & 1; + picture->concealment_motion_vectors = (buffer[3] >> 5) & 1; + picture->q_scale_type = (buffer[3] >> 4) & 1; + picture->intra_vlc_format = (buffer[3] >> 3) & 1; + + if (buffer[3] & 4) /* alternate_scan */ + picture->scan = mpeg2_scan_alt; + else + picture->scan = mpeg2_scan_norm; + + /* these are not used by the decoder */ + picture->top_field_first = buffer[3] >> 7; + picture->repeat_first_field = (buffer[3] >> 1) & 1; + picture->progressive_frame = buffer[4] >> 7; + + return 0; +} + +static int sequence_display_extension (picture_t * picture, uint8_t * buffer) { + /* FIXME: implement. */ + uint32_t bit_position; + uint32_t padding; + + bit_position = 0; + padding = get_bits(buffer, 4, &bit_position); + picture->video_format = get_bits(buffer, 3, &bit_position); + picture->colour_description = get_bits(buffer, 1, &bit_position); + if(picture->colour_description) { + picture->colour_primatives = get_bits(buffer, 8, &bit_position); + picture->transfer_characteristics = get_bits(buffer, 8, &bit_position); + picture->matrix_coefficients = get_bits(buffer, 8, &bit_position); + } + picture->display_horizontal_size = get_bits(buffer, 14, &bit_position); + padding = get_bits(buffer, 1, &bit_position); + picture->display_vertical_size = get_bits(buffer, 14, &bit_position); + +#ifdef LOG_PAN_SCAN + printf("Sequence_display_extension\n"); + printf(" video_format: %u\n", picture->video_format); + printf(" colour_description: %u\n", picture->colour_description); + if(picture->colour_description) { + printf(" colour_primatives: %u\n", picture->colour_primatives); + printf(" transfer_characteristics %u\n", picture->transfer_characteristics); + printf(" matrix_coefficients %u\n", picture->matrix_coefficients); + } + printf(" display_horizontal_size %u\n", picture->display_horizontal_size); + printf(" display_vertical_size %u\n", picture->display_vertical_size); +#endif + + return 0; +} + +static int picture_display_extension (picture_t * picture, uint8_t * buffer) { + uint32_t bit_position; + uint32_t padding; + +#ifdef LOG_PAN_SCAN + printf ("libmpeg2: picture_display_extension\n"); +#endif + + bit_position = 0; + padding = get_bits(buffer, 4, &bit_position); + picture->frame_centre_horizontal_offset = get_bits_signed(buffer, 16, &bit_position); + padding = get_bits(buffer, 1, &bit_position); + picture->frame_centre_vertical_offset = get_bits_signed(buffer, 16, &bit_position); + padding = get_bits(buffer, 1, &bit_position); + +#ifdef LOG_PAN_SCAN + printf("Pan & Scan centre (x,y) = (%d, %d)\n", + picture->frame_centre_horizontal_offset, + picture->frame_centre_vertical_offset); +#endif + + return 0; +} + +int mpeg2_header_extension (picture_t * picture, uint8_t * buffer) +{ + switch (buffer[0] & 0xf0) { + case 0x00: /* reserved */ + return 0; + + case 0x10: /* sequence extension */ + return sequence_extension (picture, buffer); + + case 0x20: /* sequence display extension for Pan & Scan */ + return sequence_display_extension (picture, buffer); + + case 0x30: /* quant matrix extension */ + return quant_matrix_extension (picture, buffer); + + case 0x40: /* copyright extension */ + return 0; + + case 0x50: /* sequence scalable extension */ + return 0; + + case 0x60: /* reserved */ + return 0; + + case 0x70: /* picture display extension for Pan & Scan */ + return picture_display_extension (picture, buffer); + + case 0x80: /* picture coding extension */ + return picture_coding_extension (picture, buffer); + + case 0x90: /* picture spacial scalable extension */ + return 0; + + case 0xA0: /* picture temporal scalable extension */ + return 0; + + case 0xB0: /* camera parameters extension */ + return 0; + + case 0xC0: /* ITU-T extension */ + return 0; + + case 0xD0: /* reserved */ + return 0; + + case 0xE0: /* reserved */ + return 0; + + case 0xF0: /* reserved */ + return 0; + } + + return 0; +} + +int mpeg2_header_group_of_pictures (picture_t * picture, uint8_t * buffer) { + uint32_t bit_position; + uint32_t padding; + bit_position = 0; + + picture->drop_frame_flag = get_bits(buffer, 1, &bit_position); + picture->time_code_hours = get_bits(buffer, 5, &bit_position); + picture->time_code_minutes = get_bits(buffer, 6, &bit_position); + padding = get_bits(buffer, 1, &bit_position); + picture->time_code_seconds = get_bits(buffer, 6, &bit_position); + picture->time_code_pictures = get_bits(buffer, 6, &bit_position); + picture->closed_gop = get_bits(buffer, 1, &bit_position); + picture->broken_link = get_bits(buffer, 1, &bit_position); + +#ifdef LOG_PAN_SCAN + printf("Group of pictures\n"); + printf(" drop_frame_flag: %u\n", picture->drop_frame_flag); + printf(" time_code: HH:MM:SS:Pictures %02u:%02u:%02u:%02u\n", + picture->time_code_hours, + picture->time_code_minutes, + picture->time_code_seconds, + picture->time_code_pictures); + printf(" closed_gop: %u\n", picture->closed_gop); + printf(" bloken_link: %u\n", picture->broken_link); +#endif + + return 0; +} + +int mpeg2_header_picture (picture_t * picture, uint8_t * buffer) +{ + picture->picture_coding_type = (buffer [1] >> 3) & 7; + picture->vbv_delay = ((buffer[1] << 13) | (buffer[2] << 5) | + (buffer[3] >> 3)) & 0xffff; + + /* forward_f_code and backward_f_code - used in mpeg1 only */ + picture->f_motion.f_code[1] = (buffer[3] >> 2) & 1; + picture->f_motion.f_code[0] = + (((buffer[3] << 1) | (buffer[4] >> 7)) & 7) - 1; + picture->b_motion.f_code[1] = (buffer[4] >> 6) & 1; + picture->b_motion.f_code[0] = ((buffer[4] >> 3) & 7) - 1; + + /* move in header_process_picture_header */ + picture->second_field = + (picture->picture_structure != FRAME_PICTURE) && + !(picture->second_field); + + return 0; +} |