/* GStreamer Adaptive Multi-Rate parser plugin * Copyright (C) 2006 Edgard Lima * Copyright (C) 2008 Nokia Corporation. All rights reserved. * * Contact: Stefan Kost * * 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. */ /** * SECTION:element-amrparse * @short_description: AMR parser * @see_also: #GstAmrnbDec, #GstAmrnbEnc * * * * This is an AMR parser capable of handling both narrow-band and wideband * formats. * * Example launch line * * * gst-launch filesrc location=abc.amr ! amrparse ! amrdec ! audioresample ! audioconvert ! alsasink * * * */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include "gstamrparse.h" static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("audio/AMR, " "rate = (int) 8000, " "channels = (int) 1;" "audio/AMR-WB, " "rate = (int) 16000, " "channels = (int) 1;") ); static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("audio/x-amr-nb-sh; audio/x-amr-wb-sh")); GST_DEBUG_CATEGORY_STATIC (gst_amrparse_debug); #define GST_CAT_DEFAULT gst_amrparse_debug static const gint block_size_nb[16] = { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 }; static const gint block_size_wb[16] = { 17, 23, 32, 36, 40, 46, 50, 58, 60, 5, 5, 0, 0, 0, 0, 0 }; /* AMR has a "hardcoded" framerate of 50fps */ #define AMR_FRAMES_PER_SECOND 50 #define AMR_FRAME_DURATION (GST_SECOND/AMR_FRAMES_PER_SECOND) #define AMR_MIME_HEADER_SIZE 9 gboolean gst_amrparse_start (GstBaseParse * parse); gboolean gst_amrparse_stop (GstBaseParse * parse); static gboolean gst_amrparse_sink_setcaps (GstBaseParse * parse, GstCaps * caps); gboolean gst_amrparse_check_valid_frame (GstBaseParse * parse, GstBuffer * buffer, guint * framesize, gint * skipsize); GstFlowReturn gst_amrparse_parse_frame (GstBaseParse * parse, GstBuffer * buffer); #define _do_init(bla) \ GST_DEBUG_CATEGORY_INIT (gst_amrparse_debug, "amrparse", 0, \ "AMR-NB audio stream parser"); GST_BOILERPLATE_FULL (GstAmrParse, gst_amrparse, GstBaseParse, GST_TYPE_BASE_PARSE, _do_init); /** * gst_amrparse_base_init: * @klass: #GstElementClass. * */ static void gst_amrparse_base_init (gpointer klass) { GstElementClass *element_class = GST_ELEMENT_CLASS (klass); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&sink_template)); gst_element_class_add_pad_template (element_class, gst_static_pad_template_get (&src_template)); gst_element_class_set_details_simple (element_class, "AMR audio stream parser", "Codec/Parser/Audio", "Adaptive Multi-Rate audio parser", "Ronald Bultje "); } /** * gst_amrparse_class_init: * @klass: GstAmrParseClass. * */ static void gst_amrparse_class_init (GstAmrParseClass * klass) { GstBaseParseClass *parse_class = GST_BASE_PARSE_CLASS (klass); parse_class->start = GST_DEBUG_FUNCPTR (gst_amrparse_start); parse_class->stop = GST_DEBUG_FUNCPTR (gst_amrparse_stop); parse_class->set_sink_caps = GST_DEBUG_FUNCPTR (gst_amrparse_sink_setcaps); parse_class->parse_frame = GST_DEBUG_FUNCPTR (gst_amrparse_parse_frame); parse_class->check_valid_frame = GST_DEBUG_FUNCPTR (gst_amrparse_check_valid_frame); } /** * gst_amrparse_init: * @amrparse: #GstAmrParse * @klass: #GstAmrParseClass. * */ static void gst_amrparse_init (GstAmrParse * amrparse, GstAmrParseClass * klass) { /* init rest */ gst_base_parse_set_min_frame_size (GST_BASE_PARSE (amrparse), 62); GST_DEBUG ("initialized"); } /** * gst_amrparse_set_src_caps: * @amrparse: #GstAmrParse. * * Set source pad caps according to current knowledge about the * audio stream. * * Returns: TRUE if caps were successfully set. */ static gboolean gst_amrparse_set_src_caps (GstAmrParse * amrparse) { GstCaps *src_caps = NULL; gboolean res = FALSE; if (amrparse->wide) { GST_DEBUG_OBJECT (amrparse, "setting srcpad caps to AMR-WB"); src_caps = gst_caps_new_simple ("audio/AMR-WB", "channels", G_TYPE_INT, 1, "rate", G_TYPE_INT, 16000, NULL); } else { GST_DEBUG_OBJECT (amrparse, "setting srcpad caps to AMR-NB"); /* Max. size of NB frame is 31 bytes, so we can set the min. frame size to 32 (+1 for next frame header) */ gst_base_parse_set_min_frame_size (GST_BASE_PARSE (amrparse), 32); src_caps = gst_caps_new_simple ("audio/AMR", "channels", G_TYPE_INT, 1, "rate", G_TYPE_INT, 8000, NULL); } gst_pad_use_fixed_caps (GST_BASE_PARSE (amrparse)->srcpad); res = gst_pad_set_caps (GST_BASE_PARSE (amrparse)->srcpad, src_caps); gst_caps_unref (src_caps); return res; } /** * gst_amrparse_sink_setcaps: * @sinkpad: GstPad * @caps: GstCaps * * Returns: TRUE on success. */ static gboolean gst_amrparse_sink_setcaps (GstBaseParse * parse, GstCaps * caps) { GstAmrParse *amrparse; GstStructure *structure; const gchar *name; amrparse = GST_AMRPARSE (parse); structure = gst_caps_get_structure (caps, 0); name = gst_structure_get_name (structure); GST_DEBUG_OBJECT (amrparse, "setcaps: %s", name); if (!strncmp (name, "audio/x-amr-wb-sh", 17)) { amrparse->block_size = block_size_wb; amrparse->wide = 1; } else if (!strncmp (name, "audio/x-amr-nb-sh", 17)) { amrparse->block_size = block_size_nb; amrparse->wide = 0; } else { GST_WARNING ("Unknown caps"); return FALSE; } amrparse->need_header = FALSE; gst_base_parse_set_frame_props (GST_BASE_PARSE (amrparse), 50, 1, 2, 2); gst_amrparse_set_src_caps (amrparse); return TRUE; } /** * gst_amrparse_parse_header: * @amrparse: #GstAmrParse * @data: Header data to be parsed. * @skipsize: Output argument where the frame size will be stored. * * Check if the given data contains an AMR mime header. * * Returns: TRUE on success. */ static gboolean gst_amrparse_parse_header (GstAmrParse * amrparse, const guint8 * data, gint * skipsize) { GST_DEBUG_OBJECT (amrparse, "Parsing header data"); if (!memcmp (data, "#!AMR-WB\n", 9)) { GST_DEBUG_OBJECT (amrparse, "AMR-WB detected"); amrparse->block_size = block_size_wb; amrparse->wide = TRUE; *skipsize = amrparse->header = 9; } else if (!memcmp (data, "#!AMR\n", 6)) { GST_DEBUG_OBJECT (amrparse, "AMR-NB detected"); amrparse->block_size = block_size_nb; amrparse->wide = FALSE; *skipsize = amrparse->header = 6; } else return FALSE; gst_amrparse_set_src_caps (amrparse); return TRUE; } /** * gst_amrparse_check_valid_frame: * @parse: #GstBaseParse. * @buffer: #GstBuffer. * @framesize: Output variable where the found frame size is put. * @skipsize: Output variable which tells how much data needs to be skipped * until a frame header is found. * * Implementation of "check_valid_frame" vmethod in #GstBaseParse class. * * Returns: TRUE if the given data contains valid frame. */ gboolean gst_amrparse_check_valid_frame (GstBaseParse * parse, GstBuffer * buffer, guint * framesize, gint * skipsize) { const guint8 *data; gint fsize, mode, dsize; GstAmrParse *amrparse; amrparse = GST_AMRPARSE (parse); data = GST_BUFFER_DATA (buffer); dsize = GST_BUFFER_SIZE (buffer); GST_LOG ("buffer: %d bytes", dsize); if (amrparse->need_header) { if (dsize >= AMR_MIME_HEADER_SIZE && gst_amrparse_parse_header (amrparse, data, skipsize)) { amrparse->need_header = FALSE; gst_base_parse_set_frame_props (GST_BASE_PARSE (amrparse), 50, 1, 2, 2); } else { GST_WARNING ("media doesn't look like a AMR format"); } /* We return FALSE, so this frame won't get pushed forward. Instead, the "skip" value is set, so next time we will receive a valid frame. */ return FALSE; } /* Does this look like a possible frame header candidate? */ if ((data[0] & 0x83) == 0) { /* Yep. Retrieve the frame size */ mode = (data[0] >> 3) & 0x0F; fsize = amrparse->block_size[mode] + 1; /* +1 for the header byte */ /* We recognize this data as a valid frame when: * - We are in sync. There is no need for extra checks then * - We are in EOS. There might not be enough data to check next frame * - Sync is lost, but the following data after this frame seem * to contain a valid header as well (and there is enough data to * perform this check) */ if (gst_base_parse_get_sync (parse) || gst_base_parse_get_drain (parse) || (dsize >= fsize && (data[fsize] & 0x83) == 0)) { *framesize = fsize; return TRUE; } } GST_LOG ("sync lost"); return FALSE; } /** * gst_amrparse_parse_frame: * @parse: #GstBaseParse. * @buffer: #GstBuffer. * * Implementation of "parse" vmethod in #GstBaseParse class. * * Returns: #GstFlowReturn defining the parsing status. */ GstFlowReturn gst_amrparse_parse_frame (GstBaseParse * parse, GstBuffer * buffer) { gst_buffer_set_caps (buffer, GST_PAD_CAPS (parse->srcpad)); return GST_FLOW_OK; } /** * gst_amrparse_start: * @parse: #GstBaseParse. * * Implementation of "start" vmethod in #GstBaseParse class. * * Returns: TRUE on success. */ gboolean gst_amrparse_start (GstBaseParse * parse) { GstAmrParse *amrparse; amrparse = GST_AMRPARSE (parse); GST_DEBUG ("start"); amrparse->need_header = TRUE; amrparse->header = 0; return TRUE; } /** * gst_amrparse_stop: * @parse: #GstBaseParse. * * Implementation of "stop" vmethod in #GstBaseParse class. * * Returns: TRUE on success. */ gboolean gst_amrparse_stop (GstBaseParse * parse) { GstAmrParse *amrparse; amrparse = GST_AMRPARSE (parse); GST_DEBUG ("stop"); amrparse->need_header = TRUE; amrparse->header = 0; return TRUE; }