Recherche avancée
Autres articles (76)
-
MediaSPIP v0.2
21 juin 2013, parMediaSPIP 0.2 est la première version de MediaSPIP stable.
Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...) -
Websites made with MediaSPIP
2 mai 2011, parThis page lists some websites based on MediaSPIP.
-
(Dés)Activation de fonctionnalités (plugins)
18 février 2011, parPour gérer l’ajout et la suppression de fonctionnalités supplémentaires (ou plugins), MediaSPIP utilise à partir de la version 0.2 SVP.
SVP permet l’activation facile de plugins depuis l’espace de configuration de MediaSPIP.
Pour y accéder, il suffit de se rendre dans l’espace de configuration puis de se rendre sur la page "Gestion des plugins".
MediaSPIP est fourni par défaut avec l’ensemble des plugins dits "compatibles", ils ont été testés et intégrés afin de fonctionner parfaitement avec chaque (...)
Sur d’autres sites (7799)
-
Revision 1cfc86ebe0 : Add unit test for x4 multi-SAD functions Update the function prototypes to matc
1er mars 2013, par John KoleszarChanged Paths : Modify /test/sad_test.cc Modify /vp9/common/vp9_rtcd_defs.sh Modify /vp9/encoder/vp9_sad_c.c Modify /vp9/encoder/vp9_variance.h Add unit test for x4 multi-SAD functions Update the function prototypes to match between VP9 and VP8. Change-Id : (...)
-
cbs_mpeg2 : Fix parsing the last unit
29 juillet 2019, par Andreas Rheinhardtcbs_mpeg2 : Fix parsing the last unit
There is one way to find out if avpriv_find_start_code has found a start
code or not : One has to check whether the state variable contains a
start code, i.e. whether the three most significant bytes are 0x00 00 01.
Checking for whether the return value is the end of the designated
buffer is not enough : If the last four bytes constitute a start code,
the return value is also the end of the buffer. This happens with
sequence_end_codes which have been ignored for exactly this reason,
although e.g. all three files used for fate tests of cbs_mpeg2 contain
sequence_end_codes.Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
-
Libavcodec : How to tell end of access unit when decoding H.264 stream
22 septembre 2011, par FlameI'm receiving H.264 video over RTP and decoding it with libavcodec. I'm unpackaging the NAL units from the RTP packets before feeding them to avcodec (including reassembling fragmentation units).
I'm trying to show effective decoding frame rate. I used to log the time after a successful decode video call where *got_picture_ptr is non-zero. So far this worked since I only ever got video where there was one slice per frame. But now I receive video where both I and P frames consist of 2 NAL units each, of types 5 and 1 respectively. Now when I feed the either slice of a frame, decode_video return that it got a picture, and the pAVFrame->coded_picture_number is increased from every slice.
How do I go about reliably finding the beginning or end of a video frame/picture/access unit ?
I've dumped out a few NAL units from the stream and run them through h264_analyze from h264bitstream.
Output from h264_analyze on 4 NAL Units
!! Found NAL at offset 695262 (0xA9BDE), size 25 (0x0019) ==================== NAL ==================== forbidden_zero_bit : 0 nal_ref_idc : 1 nal_unit_type : 7 ( Sequence parameter set ) ======= SPS ======= profile_idc : 66 constraint_set0_flag : 1 constraint_set1_flag : 1 constraint_set2_flag : 1 constraint_set3_flag : 0 reserved_zero_4bits : 0 level_idc : 32 seq_parameter_set_id : 0 chroma_format_idc : 0 residual_colour_transform_flag : 0 bit_depth_luma_minus8 : 0 bit_depth_chroma_minus8 : 0 qpprime_y_zero_transform_bypass_flag : 0 seq_scaling_matrix_present_flag : 0 log2_max_frame_num_minus4 : 12 pic_order_cnt_type : 2 log2_max_pic_order_cnt_lsb_minus4 : 0 delta_pic_order_always_zero_flag : 0 offset_for_non_ref_pic : 0 offset_for_top_to_bottom_field : 0 num_ref_frames_in_pic_order_cnt_cycle : 0 num_ref_frames : 1 gaps_in_frame_num_value_allowed_flag : 0 pic_width_in_mbs_minus1 : 79 pic_height_in_map_units_minus1 : 44 frame_mbs_only_flag : 1 mb_adaptive_frame_field_flag : 0 direct_8x8_inference_flag : 1 frame_cropping_flag : 0 frame_crop_left_offset : 0 frame_crop_right_offset : 0 frame_crop_top_offset : 0 frame_crop_bottom_offset : 0 vui_parameters_present_flag : 1 === VUI === aspect_ratio_info_present_flag : 1 aspect_ratio_idc : 1 sar_width : 0 sar_height : 0 overscan_info_present_flag : 0 overscan_appropriate_flag : 0 video_signal_type_present_flag : 1 video_format : 5 video_full_range_flag : 1 colour_description_present_flag : 0 colour_primaries : 0 transfer_characteristics : 0 matrix_coefficients : 0 chroma_loc_info_present_flag : 0 chroma_sample_loc_type_top_field : 0 chroma_sample_loc_type_bottom_field : 0 timing_info_present_flag : 1 num_units_in_tick : 1 time_scale : 25 fixed_frame_rate_flag : 0 nal_hrd_parameters_present_flag : 0 vcl_hrd_parameters_present_flag : 0 low_delay_hrd_flag : 0 pic_struct_present_flag : 0 bitstream_restriction_flag : 1 motion_vectors_over_pic_boundaries_flag : 1 max_bytes_per_pic_denom : 0 max_bits_per_mb_denom : 0 log2_max_mv_length_horizontal : 6 log2_max_mv_length_vertical : 6 num_reorder_frames : 0 max_dec_frame_buffering : 1 === HRD === cpb_cnt_minus1 : 0 bit_rate_scale : 0 cpb_size_scale : 0 initial_cpb_removal_delay_length_minus1 : 0 cpb_removal_delay_length_minus1 : 0 dpb_output_delay_length_minus1 : 0 time_offset_length : 0 !! Found NAL at offset 695290 (0xA9BFA), size 4 (0x0004) ==================== NAL ==================== forbidden_zero_bit : 0 nal_ref_idc : 1 nal_unit_type : 8 ( Picture parameter set ) ======= PPS ======= pic_parameter_set_id : 0 seq_parameter_set_id : 0 entropy_coding_mode_flag : 0 pic_order_present_flag : 0 num_slice_groups_minus1 : 0 slice_group_map_type : 0 num_ref_idx_l0_active_minus1 : 0 num_ref_idx_l1_active_minus1 : 0 weighted_pred_flag : 0 weighted_bipred_idc : 0 pic_init_qp_minus26 : 3 pic_init_qs_minus26 : 0 chroma_qp_index_offset : 0 deblocking_filter_control_present_flag : 1 constrained_intra_pred_flag : 0 redundant_pic_cnt_present_flag : 0 transform_8x8_mode_flag : 1 pic_scaling_matrix_present_flag : 0 second_chroma_qp_index_offset : 1 !! Found NAL at offset 695297 (0xA9C01), size 50725 (0xC625) ==================== NAL ==================== forbidden_zero_bit : 0 nal_ref_idc : 1 nal_unit_type : 5 ( Coded slice of an IDR picture ) ======= Slice Header ======= first_mb_in_slice : 0 slice_type : 2 ( I slice ) pic_parameter_set_id : 0 frame_num : 0 field_pic_flag : 0 bottom_field_flag : 0 idr_pic_id : 0 pic_order_cnt_lsb : 0 delta_pic_order_cnt_bottom : 0 redundant_pic_cnt : 0 direct_spatial_mv_pred_flag : 0 num_ref_idx_active_override_flag : 0 num_ref_idx_l0_active_minus1 : 0 num_ref_idx_l1_active_minus1 : 0 cabac_init_idc : 0 slice_qp_delta : 5 sp_for_switch_flag : 0 slice_qs_delta : 0 disable_deblocking_filter_idc : 0 slice_alpha_c0_offset_div2 : 0 slice_beta_offset_div2 : 0 slice_group_change_cycle : 0 === Prediction Weight Table === luma_log2_weight_denom : 0 chroma_log2_weight_denom : 0 luma_weight_l0_flag : 0 chroma_weight_l0_flag : 0 luma_weight_l1_flag : 0 chroma_weight_l1_flag : 0 === Ref Pic List Reordering === ref_pic_list_reordering_flag_l0 : 0 ref_pic_list_reordering_flag_l1 : 0 === Decoded Ref Pic Marking === no_output_of_prior_pics_flag : 0 long_term_reference_flag : 0 adaptive_ref_pic_marking_mode_flag : 0 !! Found NAL at offset 746025 (0xB6229), size 38612 (0x96D4) ==================== NAL ==================== forbidden_zero_bit : 0 nal_ref_idc : 1 nal_unit_type : 5 ( Coded slice of an IDR picture ) ======= Slice Header ======= first_mb_in_slice : 1840 slice_type : 2 ( I slice ) pic_parameter_set_id : 0 frame_num : 0 field_pic_flag : 0 bottom_field_flag : 0 idr_pic_id : 0 pic_order_cnt_lsb : 0 delta_pic_order_cnt_bottom : 0 redundant_pic_cnt : 0 direct_spatial_mv_pred_flag : 0 num_ref_idx_active_override_flag : 0 num_ref_idx_l0_active_minus1 : 0 num_ref_idx_l1_active_minus1 : 0 cabac_init_idc : 0 slice_qp_delta : 5 sp_for_switch_flag : 0 slice_qs_delta : 0 disable_deblocking_filter_idc : 0 slice_alpha_c0_offset_div2 : 0 slice_beta_offset_div2 : 0 slice_group_change_cycle : 0 === Prediction Weight Table === luma_log2_weight_denom : 0 chroma_log2_weight_denom : 0 luma_weight_l0_flag : 0 chroma_weight_l0_flag : 0 luma_weight_l1_flag : 0 chroma_weight_l1_flag : 0 === Ref Pic List Reordering === ref_pic_list_reordering_flag_l0 : 0 ref_pic_list_reordering_flag_l1 : 0 === Decoded Ref Pic Marking === no_output_of_prior_pics_flag : 0 long_term_reference_flag : 0 adaptive_ref_pic_marking_mode_flag : 0Both I slices show the frame_num = 0. The next 2 (not shown) have frame_num = 1.
Syndiquer tout le site
