/* * libzvbi -- Old raw VBI decoder * * Copyright (C) 2000, 2001, 2002 Michael H. Schimek * * 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., 51 Franklin Street, Fifth Floor, * Boston, MA 02110-1301 USA. */ /* $Id: decoder.c,v 1.25 2008-02-19 00:35:15 mschimek Exp $ */ /* Note this code is only retained for compatibility with older versions of libzvbi. vbi_raw_decoder is now just a wrapper for the new raw decoder (raw_decoder.c) and bit slicer (bit_slicer.c). We'll drop the old API in libzvbi 0.3. Other modules (e.g. io-v4l2k.c) should already use the new raw VBI decoder directly. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include "misc.h" #include "decoder.h" #include "raw_decoder.h" /** * @addtogroup Rawdec Raw VBI decoder * @ingroup Raw * @brief Converting raw VBI samples to bits and bytes. * * The libzvbi already offers hardware interfaces to obtain sliced * VBI data for further processing. However if you want to write your own * interface or decode data services not covered by libzvbi you can use * these lower level functions. */ #if 0 /* LEGACY BIT SLICER */ /* * Bit Slicer */ #define OVERSAMPLING 4 /* 1, 2, 4, 8 */ #define THRESH_FRAC 9 /* * Note this is just a template. The code is inlined, * with bpp and endian being const. * * This function translates from the image format to * plain bytes, with linear interpolation of samples. * Could be further improved with a lowpass filter. */ static inline unsigned int sample (uint8_t * raw, int offs, int bpp, int endian) { unsigned char frac = offs; int raw0, raw1; switch (bpp) { case 14: /* 1:5:5:5 LE/BE */ raw += (offs >> 8) * 2; raw0 = (raw[0 + endian] + raw[1 - endian] * 256) & 0x07C0; raw1 = (raw[2 + endian] + raw[3 - endian] * 256) & 0x07C0; return (raw1 - raw0) * frac + (raw0 << 8); case 15: /* 5:5:5:1 LE/BE */ raw += (offs >> 8) * 2; raw0 = (raw[0 + endian] + raw[1 - endian] * 256) & 0x03E0; raw1 = (raw[2 + endian] + raw[3 - endian] * 256) & 0x03E0; return (raw1 - raw0) * frac + (raw0 << 8); case 16: /* 5:6:5 LE/BE */ raw += (offs >> 8) * 2; raw0 = (raw[0 + endian] + raw[1 - endian] * 256) & 0x07E0; raw1 = (raw[2 + endian] + raw[3 - endian] * 256) & 0x07E0; return (raw1 - raw0) * frac + (raw0 << 8); default: /* 8 (intermediate bytes skipped by caller) */ raw += (offs >> 8) * bpp; return (raw[bpp] - raw[0]) * frac + (raw[0] << 8); } } /* * Note this is just a template. The code is inlined, * with bpp being const. */ static inline vbi_bool bit_slicer_tmpl (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf, int bpp, int endian) { unsigned int i, j, k; unsigned int cl = 0, thresh0 = d->thresh, tr; unsigned int c = 0, t; unsigned char b, b1 = 0; int raw0, raw1, mask; raw += d->skip; if (bpp == 14) mask = 0x07C0; else if (bpp == 15) mask = 0x03E0; else if (bpp == 16) mask = 0x07E0; for (i = d->cri_bytes; i > 0; raw += (bpp >= 14 && bpp <= 16) ? 2 : bpp, i--) { if (bpp >= 14 && bpp <= 16) { raw0 = (raw[0 + endian] + raw[1 - endian] * 256) & mask; raw1 = (raw[2 + endian] + raw[3 - endian] * 256) & mask; tr = d->thresh >> THRESH_FRAC; d->thresh += ((raw0 - tr) * (int) ABS (raw1 - raw0)) >> ((bpp == 15) ? 2 : 3); t = raw0 * OVERSAMPLING; } else { tr = d->thresh >> THRESH_FRAC; d->thresh += ((int) raw[0] - tr) * (int) ABS (raw[bpp] - raw[0]); t = raw[0] * OVERSAMPLING; } for (j = OVERSAMPLING; j > 0; j--) { b = ((t + (OVERSAMPLING / 2)) / OVERSAMPLING >= tr); if (b ^ b1) { cl = d->oversampling_rate >> 1; } else { cl += d->cri_rate; if (cl >= (unsigned int) d->oversampling_rate) { cl -= d->oversampling_rate; c = c * 2 + b; if ((c & d->cri_mask) == d->cri) { i = d->phase_shift; tr *= 256; c = 0; for (j = d->frc_bits; j > 0; j--) { c = c * 2 + (sample (raw, i, bpp, endian) >= tr); i += d->step; } if (c ^= d->frc) return FALSE; /* CRI/FRC found, now get the payload and exit */ switch (d->endian) { case 3: for (j = 0; j < (unsigned int) d->payload; j++) { c >>= 1; c += (sample (raw, i, bpp, endian) >= tr) << 7; i += d->step; if ((j & 7) == 7) *buf++ = c; } *buf = c >> ((8 - d->payload) & 7); break; case 2: for (j = 0; j < (unsigned int) d->payload; j++) { c = c * 2 + (sample (raw, i, bpp, endian) >= tr); i += d->step; if ((j & 7) == 7) *buf++ = c; } *buf = c & ((1 << (d->payload & 7)) - 1); break; case 1: for (j = d->payload; j > 0; j--) { for (k = 0; k < 8; k++) { c >>= 1; c += (sample (raw, i, bpp, endian) >= tr) << 7; i += d->step; } *buf++ = c; } break; case 0: for (j = d->payload; j > 0; j--) { for (k = 0; k < 8; k++) { c = c * 2 + (sample (raw, i, bpp, endian) >= tr); i += d->step; } *buf++ = c; } break; } return TRUE; } } } b1 = b; if (OVERSAMPLING > 1) { if (bpp >= 14 && bpp <= 16) { t += raw1; t -= raw0; } else { t += raw[bpp]; t -= raw[0]; } } } } d->thresh = thresh0; return FALSE; } static vbi_bool bit_slicer_1 (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 1, 0); } static vbi_bool bit_slicer_2 (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 2, 0); } static vbi_bool bit_slicer_3 (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 3, 0); } static vbi_bool bit_slicer_4 (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 4, 0); } static vbi_bool bit_slicer_1555_le (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 14, 0); } static vbi_bool bit_slicer_5551_le (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 15, 0); } static vbi_bool bit_slicer_565_le (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 16, 0); } static vbi_bool bit_slicer_1555_be (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 14, 1); } static vbi_bool bit_slicer_5551_be (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 15, 1); } static vbi_bool bit_slicer_565_be (vbi_bit_slicer * d, uint8_t * raw, uint8_t * buf) { return bit_slicer_tmpl (d, raw, buf, 16, 1); } /** * @param slicer Pointer to vbi_bit_slicer object to be initialized. * @param raw_samples Number of samples or pixels in one raw vbi line * later passed to vbi_bit_slice(). This limits the number of * bytes read from the sample buffer. * @param sampling_rate Raw vbi sampling rate in Hz, that is the number of * samples or pixels sampled per second by the hardware. * @param cri_rate The Clock Run In is a NRZ modulated * sequence of '0' and '1' bits prepending most data transmissions to * synchronize data acquisition circuits. This parameter gives the CRI bit * rate in Hz, that is the number of CRI bits transmitted per second. * @param bit_rate The transmission bit rate of all data bits following the CRI * in Hz. * @param cri_frc The FRaming Code usually following the CRI is a bit sequence * identifying the data service, and per libzvbi definition modulated * and transmitted at the same bit rate as the payload (however nothing * stops you from counting all nominal CRI and FRC bits as CRI). * The bit slicer compares the bits in this word, lsb last transmitted, * against the transmitted CRI and FRC. Decoding of payload starts * with the next bit after a match. * @param cri_mask Of the CRI bits in @c cri_frc, only these bits are * actually significant for a match. For instance it is wise * not to rely on the very first CRI bits transmitted. Note this * mask is not shifted left by @a frc_bits. * @param cri_bits * @param frc_bits Number of CRI and FRC bits in @a cri_frc, respectively. * Their sum is limited to 32. * @param payload Number of payload bits. Only this data * will be stored in the vbi_bit_slice() output. If this number * is no multiple of eight, the most significant bits of the * last byte are undefined. * @param modulation Modulation of the vbi data, see vbi_modulation. * @param fmt Format of the raw data, see vbi_pixfmt. * * Initializes vbi_bit_slicer object. Usually you will not use this * function but vbi_raw_decode(), the vbi image decoder which handles * all these details. */ void vbi_bit_slicer_init (vbi_bit_slicer * slicer, int raw_samples, int sampling_rate, int cri_rate, int bit_rate, unsigned int cri_frc, unsigned int cri_mask, int cri_bits, int frc_bits, int payload, vbi_modulation modulation, vbi_pixfmt fmt) { unsigned int c_mask = (unsigned int) (-(cri_bits > 0)) >> (32 - cri_bits); unsigned int f_mask = (unsigned int) (-(frc_bits > 0)) >> (32 - frc_bits); int gsh = 0; slicer->func = bit_slicer_1; switch (fmt) { case VBI_PIXFMT_RGB24: case VBI_PIXFMT_BGR24: slicer->func = bit_slicer_3; slicer->skip = 1; break; case VBI_PIXFMT_RGBA32_LE: case VBI_PIXFMT_BGRA32_LE: slicer->func = bit_slicer_4; slicer->skip = 1; break; case VBI_PIXFMT_RGBA32_BE: case VBI_PIXFMT_BGRA32_BE: slicer->func = bit_slicer_4; slicer->skip = 2; break; case VBI_PIXFMT_RGB16_LE: case VBI_PIXFMT_BGR16_LE: slicer->func = bit_slicer_565_le; gsh = 3; /* (green << 3) & 0x07E0 */ slicer->skip = 0; break; case VBI_PIXFMT_RGBA15_LE: case VBI_PIXFMT_BGRA15_LE: slicer->func = bit_slicer_5551_le; gsh = 2; /* (green << 2) & 0x03E0 */ slicer->skip = 0; break; case VBI_PIXFMT_ARGB15_LE: case VBI_PIXFMT_ABGR15_LE: slicer->func = bit_slicer_1555_le; gsh = 3; /* (green << 2) & 0x07C0 */ slicer->skip = 0; break; case VBI_PIXFMT_RGB16_BE: case VBI_PIXFMT_BGR16_BE: slicer->func = bit_slicer_565_be; gsh = 3; /* (green << 3) & 0x07E0 */ slicer->skip = 0; break; case VBI_PIXFMT_RGBA15_BE: case VBI_PIXFMT_BGRA15_BE: slicer->func = bit_slicer_5551_be; gsh = 2; /* (green << 2) & 0x03E0 */ slicer->skip = 0; break; case VBI_PIXFMT_ARGB15_BE: case VBI_PIXFMT_ABGR15_BE: slicer->func = bit_slicer_1555_be; gsh = 3; /* (green << 2) & 0x07C0 */ slicer->skip = 0; break; case VBI_PIXFMT_YUV420: slicer->func = bit_slicer_1; slicer->skip = 0; break; case VBI_PIXFMT_YUYV: case VBI_PIXFMT_YVYU: slicer->func = bit_slicer_2; slicer->skip = 0; break; case VBI_PIXFMT_UYVY: case VBI_PIXFMT_VYUY: slicer->func = bit_slicer_2; slicer->skip = 1; break; default: fprintf (stderr, "vbi_bit_slicer_init: unknown pixfmt %d\n", fmt); exit (EXIT_FAILURE); } slicer->cri_mask = cri_mask & c_mask; slicer->cri = (cri_frc >> frc_bits) & slicer->cri_mask; /* We stop searching for CRI/FRC when the payload cannot possibly fit anymore. */ slicer->cri_bytes = raw_samples - ((long long) sampling_rate * (payload + frc_bits)) / bit_rate; slicer->cri_rate = cri_rate; /* Raw vbi data is oversampled to account for low sampling rates. */ slicer->oversampling_rate = sampling_rate * OVERSAMPLING; /* 0/1 threshold */ slicer->thresh = 105 << (THRESH_FRAC + gsh); slicer->frc = cri_frc & f_mask; slicer->frc_bits = frc_bits; /* Payload bit distance in 1/256 raw samples. */ slicer->step = (int) (sampling_rate * 256.0 / bit_rate); if (payload & 7) { slicer->payload = payload; slicer->endian = 3; } else { slicer->payload = payload >> 3; slicer->endian = 1; } switch (modulation) { case VBI_MODULATION_NRZ_MSB: slicer->endian--; case VBI_MODULATION_NRZ_LSB: slicer->phase_shift = (int) (sampling_rate * 256.0 / cri_rate * .5 + sampling_rate * 256.0 / bit_rate * .5 + 128); break; case VBI_MODULATION_BIPHASE_MSB: slicer->endian--; case VBI_MODULATION_BIPHASE_LSB: /* Phase shift between the NRZ modulated CRI and the rest */ slicer->phase_shift = (int) (sampling_rate * 256.0 / cri_rate * .5 + sampling_rate * 256.0 / bit_rate * .25 + 128); break; } } #endif /** * @example examples/wss.c * WSS capture example. */ /** * @param rd Initialized vbi_raw_decoder structure. * @param raw A raw vbi image as defined in the vbi_raw_decoder structure * (rd->sampling_format, rd->bytes_per_line, rd->count[0] + rd->count[1] * scan lines). * @param out Buffer to store the decoded vbi_sliced data. Since every * vbi scan line may contain data, this must be an array of vbi_sliced * with the same number of entries as scan lines in the raw image * (rd->count[0] + rd->count[1]). * * Decode a raw vbi image, consisting of several scan lines of raw vbi data, * into sliced vbi data. The output is sorted by line number. * * Note this function attempts to learn which lines carry which data * service, or none, to speed up decoding. You should avoid using the same * vbi_raw_decoder structure for different sources. * * @return * The number of lines decoded, i. e. the number of vbi_sliced records * written. */ int vbi_raw_decode (vbi_raw_decoder * rd, uint8_t * raw, vbi_sliced * out) { vbi3_raw_decoder *rd3; unsigned int n_lines; assert (NULL != rd); assert (NULL != raw); assert (NULL != out); rd3 = (vbi3_raw_decoder *) rd->pattern; n_lines = rd->count[0] + rd->count[1]; g_mutex_lock (&rd->mutex); { n_lines = vbi3_raw_decoder_decode (rd3, out, n_lines, raw); } g_mutex_unlock (&rd->mutex); return n_lines; } /** * @param rd Initialized vbi_raw_decoder structure. * @param start Array of start line indices for both fields * @param count Array of line counts for both fields * * Grows or shrinks the internal state arrays for VBI geometry changes */ void vbi_raw_decoder_resize (vbi_raw_decoder * rd, int *start, unsigned int *count) { #if 0 /* Set but unused */ vbi_service_set service_set; #endif vbi3_raw_decoder *rd3; assert (NULL != rd); assert (NULL != start); assert (NULL != count); rd3 = (vbi3_raw_decoder *) rd->pattern; g_mutex_lock (&rd->mutex); { if ((rd->start[0] == start[0]) && (rd->start[1] == start[1]) && (rd->count[0] == (int) count[0]) && (rd->count[1] == (int) count[1])) { g_mutex_unlock (&rd->mutex); return; } rd->start[0] = start[0]; rd->start[1] = start[1]; rd->count[0] = count[0]; rd->count[1] = count[1]; #if 0 /* Set but unused */ service_set = vbi3_raw_decoder_set_sampling_par (rd3, (vbi_sampling_par *) rd, /* strict */ 0); #else vbi3_raw_decoder_set_sampling_par (rd3, (vbi_sampling_par *) rd, /* strict */ 0); #endif } g_mutex_unlock (&rd->mutex); } /** * @param rd Initialized vbi_raw_decoder structure. * @param services Set of @ref VBI_SLICED_ symbols. * * Removes one or more data services to be decoded from the * vbi_raw_decoder structure. This function can be called at any * time and does not touch sampling parameters. * * @return * Set of @ref VBI_SLICED_ symbols describing the remaining data * services that will be decoded. */ unsigned int vbi_raw_decoder_remove_services (vbi_raw_decoder * rd, unsigned int services) { vbi_service_set service_set; vbi3_raw_decoder *rd3; assert (NULL != rd); rd3 = (vbi3_raw_decoder *) rd->pattern; service_set = services; g_mutex_lock (&rd->mutex); { service_set = vbi3_raw_decoder_remove_services (rd3, service_set); } g_mutex_unlock (&rd->mutex); return service_set; } /** * @param rd Initialized vbi_raw_decoder structure. * @param services Set of @ref VBI_SLICED_ symbols. * @param strict See description of vbi_raw_decoder_add_services() * * Check which of the given services can be decoded with current capture * parameters at a given strictness level. * * @return * Subset of services actually decodable. */ unsigned int vbi_raw_decoder_check_services (vbi_raw_decoder * rd, unsigned int services, int strict) { vbi_service_set service_set; assert (NULL != rd); service_set = services; g_mutex_lock (&rd->mutex); { service_set = vbi_sampling_par_check_services ((vbi_sampling_par *) rd, service_set, strict); } g_mutex_unlock (&rd->mutex); return (unsigned int) service_set; } /** * @param rd Initialized vbi_raw_decoder structure. * @param services Set of @ref VBI_SLICED_ symbols. * @param strict A value of 0, 1 or 2 requests loose, reliable or strict * matching of sampling parameters. For example if the data service * requires knowledge of line numbers while they are not known, @c 0 * will accept the service (which may work if the scan lines are * populated in a non-confusing way) but @c 1 or @c 2 will not. If the * data service may use more lines than are sampled, @c 1 will * accept but @c 2 will not. If unsure, set to @c 1. * * After you initialized the sampling parameters in @a rd (according to * the abilities of your raw vbi source), this function adds one or more * data services to be decoded. The libzvbi raw vbi decoder can decode up * to eight data services in parallel. You can call this function while * already decoding, it does not change sampling parameters and you must * not change them either after calling this. * * @return * Set of @ref VBI_SLICED_ symbols describing the data services that actually * will be decoded. This excludes those services not decodable given * the sampling parameters in @a rd. */ unsigned int vbi_raw_decoder_add_services (vbi_raw_decoder * rd, unsigned int services, int strict) { vbi_service_set service_set; vbi3_raw_decoder *rd3; assert (NULL != rd); rd3 = (vbi3_raw_decoder *) rd->pattern; service_set = services; g_mutex_lock (&rd->mutex); { vbi3_raw_decoder_set_sampling_par (rd3, (vbi_sampling_par *) rd, strict); service_set = vbi3_raw_decoder_add_services (rd3, service_set, strict); } g_mutex_unlock (&rd->mutex); return service_set; } /** * @param rd Initialized vbi_raw_decoder structure. * @param services Set of VBI_SLICED_ symbols. Here (and only here) you * can add @c VBI_SLICED_VBI_625 or @c VBI_SLICED_VBI_525 to include all * vbi scan lines in the calculated sampling parameters. * @param scanning When 525 accept only NTSC services, when 625 * only PAL/SECAM services. When scanning is 0, determine the scanning * from the requested services, an ambiguous set will pick * a 525 or 625 line system at random. * @param max_rate If given, the highest data bit rate in Hz of all * services requested is stored here. (The sampling rate * should be at least twice as high; rd->sampling_rate will * be set to a more reasonable value of 27 MHz derived * from ITU-R Rec. 601.) * * Calculate the sampling parameters in @a rd required to receive and * decode the requested data @a services. rd->sampling_format will be * @c VBI_PIXFMT_YUV420, rd->bytes_per_line set accordingly to a * reasonable minimum. This function can be used to initialize hardware * prior to calling vbi_raw_decoder_add_service(). * * @return * Set of @ref VBI_SLICED_ symbols describing the data services covered * by the calculated sampling parameters. This excludes services the libzvbi * raw decoder cannot decode. */ unsigned int vbi_raw_decoder_parameters (vbi_raw_decoder * rd, unsigned int services, int scanning, int *max_rate) { vbi_videostd_set videostd_set; vbi_service_set service_set; switch (scanning) { case 525: videostd_set = VBI_VIDEOSTD_SET_525_60; break; case 625: videostd_set = VBI_VIDEOSTD_SET_625_50; break; default: videostd_set = 0; break; } service_set = services; g_mutex_lock (&rd->mutex); { service_set = vbi_sampling_par_from_services ((vbi_sampling_par *) rd, (unsigned int *) max_rate, videostd_set, service_set); } g_mutex_unlock (&rd->mutex); return (unsigned int) service_set; } /** * @param rd Initialized vbi_raw_decoder structure. * * Reset a vbi_raw_decoder structure. This removes * all previously added services to be decoded (if any) * but does not touch the sampling parameters. You are * free to change the sampling parameters after calling this. */ void vbi_raw_decoder_reset (vbi_raw_decoder * rd) { vbi3_raw_decoder *rd3; if (!rd) return; /* compatibility */ assert (NULL != rd); rd3 = (vbi3_raw_decoder *) rd->pattern; g_mutex_lock (&rd->mutex); { vbi3_raw_decoder_reset (rd3); } g_mutex_unlock (&rd->mutex); } /** * @param rd Pointer to initialized vbi_raw_decoder * structure, can be @c NULL. * * Free all resources associated with @a rd. */ void vbi_raw_decoder_destroy (vbi_raw_decoder * rd) { vbi3_raw_decoder *rd3; assert (NULL != rd); rd3 = (vbi3_raw_decoder *) rd->pattern; vbi3_raw_decoder_delete (rd3); g_mutex_clear (&rd->mutex); CLEAR (*rd); } /** * @param rd Pointer to a vbi_raw_decoder structure. * * Initializes a vbi_raw_decoder structure. */ void vbi_raw_decoder_init (vbi_raw_decoder * rd) { vbi3_raw_decoder *rd3; assert (NULL != rd); CLEAR (*rd); g_mutex_init (&rd->mutex); rd3 = vbi3_raw_decoder_new ( /* sampling_par */ NULL); assert (NULL != rd3); rd->pattern = (int8_t *) rd3; } GST_DEBUG_CATEGORY (libzvbi_debug); void vbi_initialize_gst_debug (void) { GST_DEBUG_CATEGORY_INIT (libzvbi_debug, "libzvbi", 0, "libzvbi"); } /* Local variables: c-set-style: K&R c-basic-offset: 8 End: */