1 /* GStreamer Adaptive Multi-Rate parser plugin
2 * Copyright (C) 2006 Edgard Lima <edgard.lima@indt.org.br>
3 * Copyright (C) 2008 Nokia Corporation. All rights reserved.
5 * Contact: Stefan Kost <stefan.kost@nokia.com>
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
24 * SECTION:element-amrparse
25 * @short_description: AMR parser
26 * @see_also: #GstAmrnbDec, #GstAmrnbEnc
28 * This is an AMR parser capable of handling both narrow-band and wideband
32 * <title>Example launch line</title>
34 * gst-launch-1.0 filesrc location=abc.amr ! amrparse ! amrdec ! audioresample ! audioconvert ! alsasink
45 #include "gstamrparse.h"
46 #include <gst/pbutils/pbutils.h>
48 static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
51 GST_STATIC_CAPS ("audio/AMR, " "rate = (int) 8000, " "channels = (int) 1;"
52 "audio/AMR-WB, " "rate = (int) 16000, " "channels = (int) 1;")
55 static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
58 GST_STATIC_CAPS ("audio/x-amr-nb-sh; audio/x-amr-wb-sh"));
60 GST_DEBUG_CATEGORY_STATIC (amrparse_debug);
61 #define GST_CAT_DEFAULT amrparse_debug
63 static const gint block_size_nb[16] =
64 { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 };
66 static const gint block_size_wb[16] =
67 { 17, 23, 32, 36, 40, 46, 50, 58, 60, 5, -1, -1, -1, -1, 0, 0 };
69 /* AMR has a "hardcoded" framerate of 50fps */
70 #define AMR_FRAMES_PER_SECOND 50
71 #define AMR_FRAME_DURATION (GST_SECOND/AMR_FRAMES_PER_SECOND)
72 #define AMR_MIME_HEADER_SIZE 9
74 static gboolean gst_amr_parse_start (GstBaseParse * parse);
75 static gboolean gst_amr_parse_stop (GstBaseParse * parse);
77 static gboolean gst_amr_parse_sink_setcaps (GstBaseParse * parse,
79 static GstCaps *gst_amr_parse_sink_getcaps (GstBaseParse * parse,
82 static GstFlowReturn gst_amr_parse_handle_frame (GstBaseParse * parse,
83 GstBaseParseFrame * frame, gint * skipsize);
84 static GstFlowReturn gst_amr_parse_pre_push_frame (GstBaseParse * parse,
85 GstBaseParseFrame * frame);
87 G_DEFINE_TYPE (GstAmrParse, gst_amr_parse, GST_TYPE_BASE_PARSE);
90 * gst_amr_parse_class_init:
91 * @klass: GstAmrParseClass.
95 gst_amr_parse_class_init (GstAmrParseClass * klass)
97 GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
98 GstBaseParseClass *parse_class = GST_BASE_PARSE_CLASS (klass);
100 GST_DEBUG_CATEGORY_INIT (amrparse_debug, "amrparse", 0,
101 "AMR-NB audio stream parser");
103 gst_element_class_add_pad_template (element_class,
104 gst_static_pad_template_get (&sink_template));
105 gst_element_class_add_pad_template (element_class,
106 gst_static_pad_template_get (&src_template));
108 gst_element_class_set_static_metadata (element_class,
109 "AMR audio stream parser", "Codec/Parser/Audio",
110 "Adaptive Multi-Rate audio parser",
111 "Ronald Bultje <rbultje@ronald.bitfreak.net>");
113 parse_class->start = GST_DEBUG_FUNCPTR (gst_amr_parse_start);
114 parse_class->stop = GST_DEBUG_FUNCPTR (gst_amr_parse_stop);
115 parse_class->set_sink_caps = GST_DEBUG_FUNCPTR (gst_amr_parse_sink_setcaps);
116 parse_class->get_sink_caps = GST_DEBUG_FUNCPTR (gst_amr_parse_sink_getcaps);
117 parse_class->handle_frame = GST_DEBUG_FUNCPTR (gst_amr_parse_handle_frame);
118 parse_class->pre_push_frame =
119 GST_DEBUG_FUNCPTR (gst_amr_parse_pre_push_frame);
124 * gst_amr_parse_init:
125 * @amrparse: #GstAmrParse
126 * @klass: #GstAmrParseClass.
130 gst_amr_parse_init (GstAmrParse * amrparse)
133 gst_base_parse_set_min_frame_size (GST_BASE_PARSE (amrparse), 62);
134 GST_DEBUG ("initialized");
135 GST_PAD_SET_ACCEPT_INTERSECT (GST_BASE_PARSE_SINK_PAD (amrparse));
140 * gst_amr_parse_set_src_caps:
141 * @amrparse: #GstAmrParse.
143 * Set source pad caps according to current knowledge about the
146 * Returns: TRUE if caps were successfully set.
149 gst_amr_parse_set_src_caps (GstAmrParse * amrparse)
151 GstCaps *src_caps = NULL;
152 gboolean res = FALSE;
154 if (amrparse->wide) {
155 GST_DEBUG_OBJECT (amrparse, "setting srcpad caps to AMR-WB");
156 src_caps = gst_caps_new_simple ("audio/AMR-WB",
157 "channels", G_TYPE_INT, 1, "rate", G_TYPE_INT, 16000, NULL);
159 GST_DEBUG_OBJECT (amrparse, "setting srcpad caps to AMR-NB");
160 /* Max. size of NB frame is 31 bytes, so we can set the min. frame
161 size to 32 (+1 for next frame header) */
162 gst_base_parse_set_min_frame_size (GST_BASE_PARSE (amrparse), 32);
163 src_caps = gst_caps_new_simple ("audio/AMR",
164 "channels", G_TYPE_INT, 1, "rate", G_TYPE_INT, 8000, NULL);
166 gst_pad_use_fixed_caps (GST_BASE_PARSE (amrparse)->srcpad);
167 res = gst_pad_set_caps (GST_BASE_PARSE (amrparse)->srcpad, src_caps);
168 gst_caps_unref (src_caps);
174 * gst_amr_parse_sink_setcaps:
178 * Returns: TRUE on success.
181 gst_amr_parse_sink_setcaps (GstBaseParse * parse, GstCaps * caps)
183 GstAmrParse *amrparse;
184 GstStructure *structure;
187 amrparse = GST_AMR_PARSE (parse);
188 structure = gst_caps_get_structure (caps, 0);
189 name = gst_structure_get_name (structure);
191 GST_DEBUG_OBJECT (amrparse, "setcaps: %s", name);
193 if (!strncmp (name, "audio/x-amr-wb-sh", 17)) {
194 amrparse->block_size = block_size_wb;
196 } else if (!strncmp (name, "audio/x-amr-nb-sh", 17)) {
197 amrparse->block_size = block_size_nb;
200 GST_WARNING ("Unknown caps");
204 amrparse->need_header = FALSE;
205 gst_base_parse_set_frame_rate (GST_BASE_PARSE (amrparse), 50, 1, 2, 2);
206 gst_amr_parse_set_src_caps (amrparse);
211 * gst_amr_parse_parse_header:
212 * @amrparse: #GstAmrParse
213 * @data: Header data to be parsed.
214 * @skipsize: Output argument where the frame size will be stored.
216 * Check if the given data contains an AMR mime header.
218 * Returns: TRUE on success.
221 gst_amr_parse_parse_header (GstAmrParse * amrparse,
222 const guint8 * data, gint * skipsize)
224 GST_DEBUG_OBJECT (amrparse, "Parsing header data");
226 if (!memcmp (data, "#!AMR-WB\n", 9)) {
227 GST_DEBUG_OBJECT (amrparse, "AMR-WB detected");
228 amrparse->block_size = block_size_wb;
229 amrparse->wide = TRUE;
230 *skipsize = amrparse->header = 9;
231 } else if (!memcmp (data, "#!AMR\n", 6)) {
232 GST_DEBUG_OBJECT (amrparse, "AMR-NB detected");
233 amrparse->block_size = block_size_nb;
234 amrparse->wide = FALSE;
235 *skipsize = amrparse->header = 6;
239 gst_amr_parse_set_src_caps (amrparse);
245 * gst_amr_parse_check_valid_frame:
246 * @parse: #GstBaseParse.
247 * @buffer: #GstBuffer.
248 * @framesize: Output variable where the found frame size is put.
249 * @skipsize: Output variable which tells how much data needs to be skipped
250 * until a frame header is found.
252 * Implementation of "check_valid_frame" vmethod in #GstBaseParse class.
254 * Returns: TRUE if the given data contains valid frame.
257 gst_amr_parse_handle_frame (GstBaseParse * parse,
258 GstBaseParseFrame * frame, gint * skipsize)
262 gint fsize = 0, mode, dsize;
263 GstAmrParse *amrparse;
264 GstFlowReturn ret = GST_FLOW_OK;
265 gboolean found = FALSE;
267 amrparse = GST_AMR_PARSE (parse);
268 buffer = frame->buffer;
270 gst_buffer_map (buffer, &map, GST_MAP_READ);
273 GST_LOG ("buffer: %d bytes", dsize);
275 if (amrparse->need_header) {
276 if (dsize >= AMR_MIME_HEADER_SIZE &&
277 gst_amr_parse_parse_header (amrparse, map.data, skipsize)) {
278 amrparse->need_header = FALSE;
279 gst_base_parse_set_frame_rate (GST_BASE_PARSE (amrparse), 50, 1, 2, 2);
281 GST_WARNING ("media doesn't look like a AMR format");
283 /* We return FALSE, so this frame won't get pushed forward. Instead,
284 the "skip" value is set, so next time we will receive a valid frame. */
289 /* Does this look like a possible frame header candidate? */
290 if ((map.data[0] & 0x83) == 0) {
291 /* Yep. Retrieve the frame size */
292 mode = (map.data[0] >> 3) & 0x0F;
293 fsize = amrparse->block_size[mode] + 1; /* +1 for the header byte */
295 /* We recognize this data as a valid frame when:
296 * - We are in sync. There is no need for extra checks then
297 * - We are in EOS. There might not be enough data to check next frame
298 * - Sync is lost, but the following data after this frame seem
299 * to contain a valid header as well (and there is enough data to
300 * perform this check)
304 /* in sync, no further check */
305 if (!GST_BASE_PARSE_LOST_SYNC (parse)) {
307 } else if (dsize > fsize) {
308 /* enough data, check for next sync */
309 if ((map.data[fsize] & 0x83) == 0)
311 } else if (GST_BASE_PARSE_DRAINING (parse)) {
312 /* not enough, but draining, so ok */
319 gst_buffer_unmap (buffer, &map);
321 if (found && fsize <= map.size) {
322 ret = gst_base_parse_finish_frame (parse, frame, fsize);
329 * gst_amr_parse_start:
330 * @parse: #GstBaseParse.
332 * Implementation of "start" vmethod in #GstBaseParse class.
334 * Returns: TRUE on success.
337 gst_amr_parse_start (GstBaseParse * parse)
339 GstAmrParse *amrparse;
341 amrparse = GST_AMR_PARSE (parse);
343 amrparse->need_header = TRUE;
344 amrparse->header = 0;
345 amrparse->sent_codec_tag = FALSE;
351 * gst_amr_parse_stop:
352 * @parse: #GstBaseParse.
354 * Implementation of "stop" vmethod in #GstBaseParse class.
356 * Returns: TRUE on success.
359 gst_amr_parse_stop (GstBaseParse * parse)
361 GstAmrParse *amrparse;
363 amrparse = GST_AMR_PARSE (parse);
365 amrparse->need_header = TRUE;
366 amrparse->header = 0;
371 gst_amr_parse_sink_getcaps (GstBaseParse * parse, GstCaps * filter)
373 GstCaps *peercaps, *templ;
377 templ = gst_pad_get_pad_template_caps (GST_BASE_PARSE_SINK_PAD (parse));
378 peercaps = gst_pad_peer_query_caps (GST_BASE_PARSE_SRC_PAD (parse), filter);
383 /* Rename structure names */
384 peercaps = gst_caps_make_writable (peercaps);
385 n = gst_caps_get_size (peercaps);
386 for (i = 0; i < n; i++) {
387 GstStructure *s = gst_caps_get_structure (peercaps, i);
389 if (gst_structure_has_name (s, "audio/AMR"))
390 gst_structure_set_name (s, "audio/x-amr-nb-sh");
392 gst_structure_set_name (s, "audio/x-amr-wb-sh");
395 res = gst_caps_intersect_full (peercaps, templ, GST_CAPS_INTERSECT_FIRST);
396 gst_caps_unref (peercaps);
397 res = gst_caps_make_writable (res);
398 /* Append the template caps because we still want to accept
399 * caps without any fields in the case upstream does not
402 gst_caps_append (res, templ);
408 GstCaps *intersection;
411 gst_caps_intersect_full (filter, res, GST_CAPS_INTERSECT_FIRST);
412 gst_caps_unref (res);
420 gst_amr_parse_pre_push_frame (GstBaseParse * parse, GstBaseParseFrame * frame)
422 GstAmrParse *amrparse = GST_AMR_PARSE (parse);
424 if (!amrparse->sent_codec_tag) {
428 taglist = gst_tag_list_new_empty ();
431 caps = gst_pad_get_current_caps (GST_BASE_PARSE_SRC_PAD (parse));
432 gst_pb_utils_add_codec_description_to_tag_list (taglist,
433 GST_TAG_AUDIO_CODEC, caps);
434 gst_caps_unref (caps);
436 gst_pad_push_event (GST_BASE_PARSE_SRC_PAD (amrparse),
437 gst_event_new_tag (taglist));
439 /* also signals the end of first-frame processing */
440 amrparse->sent_codec_tag = TRUE;