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Autres articles (109)
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Des sites réalisés avec MediaSPIP
2 mai 2011, parCette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page. -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...) -
De l’upload à la vidéo finale [version standalone]
31 janvier 2010, parLe chemin d’un document audio ou vidéo dans SPIPMotion est divisé en trois étapes distinctes.
Upload et récupération d’informations de la vidéo source
Dans un premier temps, il est nécessaire de créer un article SPIP et de lui joindre le document vidéo "source".
Au moment où ce document est joint à l’article, deux actions supplémentaires au comportement normal sont exécutées : La récupération des informations techniques des flux audio et video du fichier ; La génération d’une vignette : extraction d’une (...)
Sur d’autres sites (13082)
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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 : 0
Both I slices show the frame_num = 0. The next 2 (not shown) have frame_num = 1.
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Stream ogv video while it is being converted
15 juin 2012, par EshMy question is how to stream an ogv video while it is being converted.
For example, I have an html page that show a html5 video that is like this :
<video>
<source src="some_url_to_video_src" type="'video/ogg'"></source>
</video>The video source here should be converted from an h264 video file located on the same server. I want to let clients be able to play the ogv video while it is being converted from the h264 file.
As I did some homework, this process could be done via ffmpeg streaming, anyone know the parameters I should use and any modification I should do in the above code as well ? A detailed answer will be much appreciated.
Thanks
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Commandline video/image crossfading
11 juin 2012, par testerI have a
test.avi
usingffmpeg
ormencoder
or some other commandline utility,
I want to takesplash.png
put it at the beginning of the video,
fade it out, show test.avi, then at the end of test.avi, fade splash.png back in.How would I go about doing this ?