• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* Gstreamer
2  * Copyright (C) <2011> Intel Corporation
3  * Copyright (C) <2011> Collabora Ltd.
4  * Copyright (C) <2011> Thibault Saunier <thibault.saunier@collabora.com>
5  *
6  * Some bits C-c,C-v'ed and s/4/3 from h264parse and videoparsers/h264parse.c:
7  *    Copyright (C) <2010> Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
8  *    Copyright (C) <2010> Collabora Multimedia
9  *    Copyright (C) <2010> Nokia Corporation
10  *
11  *    (C) 2005 Michal Benes <michal.benes@itonis.tv>
12  *    (C) 2008 Wim Taymans <wim.taymans@gmail.com>
13  *
14  * This library is free software; you can redistribute it and/or
15  * modify it under the terms of the GNU Library General Public
16  * License as published by the Free Software Foundation; either
17  * version 2 of the License, or (at your option) any later version.
18  *
19  * This library is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
22  * Library General Public License for more details.
23  *
24  * You should have received a copy of the GNU Library General Public
25  * License along with this library; if not, write to the
26  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
27  * Boston, MA 02110-1301, USA.
28  */
29 
30 /**
31  * Common code for NAL parsing from h264 and h265 parsers.
32  */
33 
34 #ifdef HAVE_CONFIG_H
35 #  include "config.h"
36 #endif
37 
38 #include <gst/base/gstbytereader.h>
39 #include <gst/base/gstbitreader.h>
40 #include <gst/base/gstbitwriter.h>
41 #include <string.h>
42 
43 guint ceil_log2 (guint32 v);
44 
45 typedef struct
46 {
47   const guint8 *data;
48   guint size;
49 
50   guint n_epb;                  /* Number of emulation prevention bytes */
51   guint byte;                   /* Byte position */
52   guint bits_in_cache;          /* bitpos in the cache of next bit */
53   guint8 first_byte;
54   guint32 epb_cache;            /* cache 3 bytes to check emulation prevention bytes */
55   guint64 cache;                /* cached bytes */
56 } NalReader;
57 
58 typedef struct
59 {
60   GstBitWriter bw;
61 
62   guint nal_prefix_size;
63   gboolean packetized;
64 } NalWriter;
65 
66 G_GNUC_INTERNAL
67 void nal_reader_init (NalReader * nr, const guint8 * data, guint size);
68 
69 G_GNUC_INTERNAL
70 gboolean nal_reader_read (NalReader * nr, guint nbits);
71 
72 G_GNUC_INTERNAL
73 gboolean nal_reader_skip (NalReader * nr, guint nbits);
74 
75 G_GNUC_INTERNAL
76 gboolean nal_reader_skip_long (NalReader * nr, guint nbits);
77 
78 G_GNUC_INTERNAL
79 guint nal_reader_get_pos (const NalReader * nr);
80 
81 G_GNUC_INTERNAL
82 guint nal_reader_get_remaining (const NalReader * nr);
83 
84 G_GNUC_INTERNAL
85 guint nal_reader_get_epb_count (const NalReader * nr);
86 
87 G_GNUC_INTERNAL
88 gboolean nal_reader_is_byte_aligned (NalReader * nr);
89 
90 G_GNUC_INTERNAL
91 gboolean nal_reader_has_more_data (NalReader * nr);
92 
93 #define NAL_READER_READ_BITS_H(bits) \
94 G_GNUC_INTERNAL \
95 gboolean nal_reader_get_bits_uint##bits (NalReader *nr, guint##bits *val, guint nbits)
96 
97 NAL_READER_READ_BITS_H (8);
98 NAL_READER_READ_BITS_H (16);
99 NAL_READER_READ_BITS_H (32);
100 
101 #define NAL_READER_PEEK_BITS_H(bits) \
102 G_GNUC_INTERNAL \
103 gboolean nal_reader_peek_bits_uint##bits (const NalReader *nr, guint##bits *val, guint nbits)
104 
105 NAL_READER_PEEK_BITS_H (8);
106 
107 G_GNUC_INTERNAL
108 gboolean nal_reader_get_ue (NalReader * nr, guint32 * val);
109 
110 G_GNUC_INTERNAL
111 gboolean nal_reader_get_se (NalReader * nr, gint32 * val);
112 
113 #define CHECK_ALLOWED_MAX_WITH_DEBUG(dbg, val, max) { \
114   if (val > max) { \
115     GST_WARNING ("value for '" dbg "' greater than max. value: %d, max %d", \
116                      val, max); \
117     goto error; \
118   } \
119 }
120 #define CHECK_ALLOWED_MAX(val, max) \
121   CHECK_ALLOWED_MAX_WITH_DEBUG (G_STRINGIFY (val), val, max)
122 
123 #define CHECK_ALLOWED_WITH_DEBUG(dbg, val, min, max) { \
124   if (val < min || val > max) { \
125     GST_WARNING ("value for '" dbg "' not in allowed range. value: %d, range %d-%d", \
126                      val, min, max); \
127     goto error; \
128   } \
129 }
130 #define CHECK_ALLOWED(val, min, max) \
131   CHECK_ALLOWED_WITH_DEBUG (G_STRINGIFY (val), val, min, max)
132 
133 #define READ_UINT8(nr, val, nbits) { \
134   if (!nal_reader_get_bits_uint8 (nr, &val, nbits)) { \
135     GST_WARNING ("failed to read uint8 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
136     goto error; \
137   } \
138 }
139 
140 #define READ_UINT16(nr, val, nbits) { \
141   if (!nal_reader_get_bits_uint16 (nr, &val, nbits)) { \
142   GST_WARNING ("failed to read uint16 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
143     goto error; \
144   } \
145 }
146 
147 #define READ_UINT32(nr, val, nbits) { \
148   if (!nal_reader_get_bits_uint32 (nr, &val, nbits)) { \
149   GST_WARNING ("failed to read uint32 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
150     goto error; \
151   } \
152 }
153 
154 #define READ_UINT64(nr, val, nbits) { \
155   if (!nal_reader_get_bits_uint64 (nr, &val, nbits)) { \
156     GST_WARNING ("failed to read uint32 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
157     goto error; \
158   } \
159 }
160 
161 #define READ_UE(nr, val) { \
162   if (!nal_reader_get_ue (nr, &val)) { \
163     GST_DEBUG ("failed to read UE for '" G_STRINGIFY (val) "'"); \
164     goto error; \
165   } \
166 }
167 
168 #define READ_UE_ALLOWED(nr, val, min, max) { \
169   guint32 tmp; \
170   READ_UE (nr, tmp); \
171   CHECK_ALLOWED_WITH_DEBUG (G_STRINGIFY (val), tmp, min, max); \
172   val = tmp; \
173 }
174 
175 #define READ_UE_MAX(nr, val, max) { \
176   guint32 tmp; \
177   READ_UE (nr, tmp); \
178   CHECK_ALLOWED_MAX_WITH_DEBUG (G_STRINGIFY (val), tmp, max); \
179   val = tmp; \
180 }
181 
182 #define READ_SE(nr, val) { \
183   if (!nal_reader_get_se (nr, &val)) { \
184     GST_WARNING ("failed to read SE for '" G_STRINGIFY (val) "'"); \
185     goto error; \
186   } \
187 }
188 
189 #define READ_SE_ALLOWED(nr, val, min, max) { \
190   gint32 tmp; \
191   READ_SE (nr, tmp); \
192   CHECK_ALLOWED_WITH_DEBUG (G_STRINGIFY (val), tmp, min, max); \
193   val = tmp; \
194 }
195 
196 G_GNUC_INTERNAL
197 gint scan_for_start_codes (const guint8 * data, guint size);
198 
199 G_GNUC_INTERNAL
200 void nal_writer_init (NalWriter * nw, guint nal_prefix_size, gboolean packetized);
201 
202 G_GNUC_INTERNAL
203 void nal_writer_reset (NalWriter * nw);
204 
205 G_GNUC_INTERNAL
206 gboolean nal_writer_do_rbsp_trailing_bits (NalWriter * nw);
207 
208 G_GNUC_INTERNAL
209 GstMemory * nal_writer_reset_and_get_memory (NalWriter * nw);
210 
211 G_GNUC_INTERNAL
212 gboolean nal_writer_put_bits_uint8 (NalWriter * nw, guint8 value, guint nbits);
213 
214 G_GNUC_INTERNAL
215 gboolean nal_writer_put_bits_uint16 (NalWriter * nw, guint16 value, guint nbits);
216 
217 G_GNUC_INTERNAL
218 gboolean nal_writer_put_bits_uint32 (NalWriter * nw, guint32 value, guint nbits);
219 
220 G_GNUC_INTERNAL
221 gboolean nal_writer_put_bytes (NalWriter * nw, const guint8 * data, guint nbytes);
222 
223 G_GNUC_INTERNAL
224 gboolean nal_writer_put_ue (NalWriter * nw, guint32 value);
225 
226 G_GNUC_INTERNAL
227 gboolean count_exp_golomb_bits (guint32 value, guint * leading_zeros, guint * rest);
228 
229 #define WRITE_UINT8(nw, val, nbits) { \
230   if (!nal_writer_put_bits_uint8 (nw, val, nbits)) { \
231     GST_WARNING ("failed to write uint8 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
232     goto error; \
233   } \
234 }
235 
236 #define WRITE_UINT16(nw, val, nbits) { \
237   if (!nal_writer_put_bits_uint16 (nw, val, nbits)) { \
238     GST_WARNING ("failed to write uint16 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
239     goto error; \
240   } \
241 }
242 
243 #define WRITE_UINT32(nw, val, nbits) { \
244   if (!nal_writer_put_bits_uint32 (nw, val, nbits)) { \
245     GST_WARNING ("failed to write uint32 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
246     goto error; \
247   } \
248 }
249 
250 #define WRITE_BYTES(nw, data, nbytes) { \
251   if (!nal_writer_put_bytes (nw, data, nbytes)) { \
252     GST_WARNING ("failed to write bytes for '" G_STRINGIFY (val) "', nbits: %d", nbytes); \
253     goto error; \
254   } \
255 }
256 
257 #define WRITE_UE(nw, val) { \
258   if (!nal_writer_put_ue (nw, val)) { \
259     GST_WARNING ("failed to write ue for '" G_STRINGIFY (val) "'"); \
260     goto error; \
261   } \
262 }
263