avcodec/aacps: Factor out code shared by float and fixed point decoder

Saves about 7KiB.

Reviewed-by: Lynne <dev@lynne.ee>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

1 files changed, 336 insertions, 0 deletions

diff --git a/libavcodec/aacps_common.c b/libavcodec/aacps_common.c
new file mode 100644
index 0000000000..ecc220f94b
--- /dev/null
+++ b/libavcodec/aacps_common.c
@@ -0,0 +1,336 @@
+/*
+ * Functions common to fixed/float MPEG-4 Parametric Stereo decoding
+ * Copyright (c) 2010 Alex Converse <alex.converse@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include "libavutil/common.h"
+#include "libavutil/thread.h"
+#include "aacps.h"
+#include "get_bits.h"
+#include "aacpsdata.c"
+
+static const int8_t num_env_tab[2][4] = {
+    { 0, 1, 2, 4, },
+    { 1, 2, 3, 4, },
+};
+
+static const int8_t nr_iidicc_par_tab[] = {
+    10, 20, 34, 10, 20, 34,
+};
+
+static const int8_t nr_iidopd_par_tab[] = {
+     5, 11, 17,  5, 11, 17,
+};
+
+enum {
+    huff_iid_df1,
+    huff_iid_dt1,
+    huff_iid_df0,
+    huff_iid_dt0,
+    huff_icc_df,
+    huff_icc_dt,
+    huff_ipd_df,
+    huff_ipd_dt,
+    huff_opd_df,
+    huff_opd_dt,
+};
+
+static const int huff_iid[] = {
+    huff_iid_df0,
+    huff_iid_df1,
+    huff_iid_dt0,
+    huff_iid_dt1,
+};
+
+static VLC vlc_ps[10];
+
+#define READ_PAR_DATA(PAR, OFFSET, MASK, ERR_CONDITION) \
+/** \
+ * Read Inter-channel Intensity Difference/Inter-Channel Coherence/ \
+ * Inter-channel Phase Difference/Overall Phase Difference parameters from the \
+ * bitstream. \
+ * \
+ * @param avctx contains the current codec context \
+ * @param gb    pointer to the input bitstream \
+ * @param ps    pointer to the Parametric Stereo context \
+ * @param PAR   pointer to the parameter to be read \
+ * @param e     envelope to decode \
+ * @param dt    1: time delta-coded, 0: frequency delta-coded \
+ */ \
+static int read_ ## PAR ## _data(AVCodecContext *avctx, GetBitContext *gb, PSCommonContext *ps, \
+                        int8_t (*PAR)[PS_MAX_NR_IIDICC], int table_idx, int e, int dt) \
+{ \
+    int b, num = ps->nr_ ## PAR ## _par; \
+    VLC_TYPE (*vlc_table)[2] = vlc_ps[table_idx].table; \
+    if (dt) { \
+        int e_prev = e ? e - 1 : ps->num_env_old - 1; \
+        e_prev = FFMAX(e_prev, 0); \
+        for (b = 0; b < num; b++) { \
+            int val = PAR[e_prev][b] + get_vlc2(gb, vlc_table, 9, 3) - OFFSET; \
+            if (MASK) val &= MASK; \
+            PAR[e][b] = val; \
+            if (ERR_CONDITION) \
+                goto err; \
+        } \
+    } else { \
+        int val = 0; \
+        for (b = 0; b < num; b++) { \
+            val += get_vlc2(gb, vlc_table, 9, 3) - OFFSET; \
+            if (MASK) val &= MASK; \
+            PAR[e][b] = val; \
+            if (ERR_CONDITION) \
+                goto err; \
+        } \
+    } \
+    return 0; \
+err: \
+    av_log(avctx, AV_LOG_ERROR, "illegal "#PAR"\n"); \
+    return AVERROR_INVALIDDATA; \
+}
+
+READ_PAR_DATA(iid,    huff_offset[table_idx],    0, FFABS(ps->iid_par[e][b]) > 7 + 8 * ps->iid_quant)
+READ_PAR_DATA(icc,    huff_offset[table_idx],    0, ps->icc_par[e][b] > 7U)
+READ_PAR_DATA(ipdopd,                      0, 0x07, 0)
+
+static int ps_read_extension_data(GetBitContext *gb, PSCommonContext *ps,
+                                  int ps_extension_id)
+{
+    int e;
+    int count = get_bits_count(gb);
+
+    if (ps_extension_id)
+        return 0;
+
+    ps->enable_ipdopd = get_bits1(gb);
+    if (ps->enable_ipdopd) {
+        for (e = 0; e < ps->num_env; e++) {
+            int dt = get_bits1(gb);
+            read_ipdopd_data(NULL, gb, ps, ps->ipd_par, dt ? huff_ipd_dt : huff_ipd_df, e, dt);
+            dt = get_bits1(gb);
+            read_ipdopd_data(NULL, gb, ps, ps->opd_par, dt ? huff_opd_dt : huff_opd_df, e, dt);
+        }
+    }
+    skip_bits1(gb);      //reserved_ps
+    return get_bits_count(gb) - count;
+}
+
+int ff_ps_read_data(AVCodecContext *avctx, GetBitContext *gb_host,
+                    PSCommonContext *ps, int bits_left)
+{
+    int e;
+    int bit_count_start = get_bits_count(gb_host);
+    int header;
+    int bits_consumed;
+    GetBitContext gbc = *gb_host, *gb = &gbc;
+
+    header = get_bits1(gb);
+    if (header) {     //enable_ps_header
+        ps->enable_iid = get_bits1(gb);
+        if (ps->enable_iid) {
+            int iid_mode = get_bits(gb, 3);
+            if (iid_mode > 5) {
+                av_log(avctx, AV_LOG_ERROR, "iid_mode %d is reserved.\n",
+                       iid_mode);
+                goto err;
+            }
+            ps->nr_iid_par    = nr_iidicc_par_tab[iid_mode];
+            ps->iid_quant     = iid_mode > 2;
+            ps->nr_ipdopd_par = nr_iidopd_par_tab[iid_mode];
+        }
+        ps->enable_icc = get_bits1(gb);
+        if (ps->enable_icc) {
+            ps->icc_mode = get_bits(gb, 3);
+            if (ps->icc_mode > 5) {
+                av_log(avctx, AV_LOG_ERROR, "icc_mode %d is reserved.\n",
+                       ps->icc_mode);
+                goto err;
+            }
+            ps->nr_icc_par = nr_iidicc_par_tab[ps->icc_mode];
+        }
+        ps->enable_ext = get_bits1(gb);
+    }
+
+    ps->frame_class = get_bits1(gb);
+    ps->num_env_old = ps->num_env;
+    ps->num_env     = num_env_tab[ps->frame_class][get_bits(gb, 2)];
+
+    ps->border_position[0] = -1;
+    if (ps->frame_class) {
+        for (e = 1; e <= ps->num_env; e++) {
+            ps->border_position[e] = get_bits(gb, 5);
+            if (ps->border_position[e] < ps->border_position[e-1]) {
+                av_log(avctx, AV_LOG_ERROR, "border_position non monotone.\n");
+                goto err;
+            }
+        }
+    } else
+        for (e = 1; e <= ps->num_env; e++)
+            ps->border_position[e] = (e * numQMFSlots >> ff_log2_tab[ps->num_env]) - 1;
+
+    if (ps->enable_iid) {
+        for (e = 0; e < ps->num_env; e++) {
+            int dt = get_bits1(gb);
+            if (read_iid_data(avctx, gb, ps, ps->iid_par, huff_iid[2*dt+ps->iid_quant], e, dt))
+                goto err;
+        }
+    } else
+        memset(ps->iid_par, 0, sizeof(ps->iid_par));
+
+    if (ps->enable_icc)
+        for (e = 0; e < ps->num_env; e++) {
+            int dt = get_bits1(gb);
+            if (read_icc_data(avctx, gb, ps, ps->icc_par, dt ? huff_icc_dt : huff_icc_df, e, dt))
+                goto err;
+        }
+    else
+        memset(ps->icc_par, 0, sizeof(ps->icc_par));
+
+    if (ps->enable_ext) {
+        int cnt = get_bits(gb, 4);
+        if (cnt == 15) {
+            cnt += get_bits(gb, 8);
+        }
+        cnt *= 8;
+        while (cnt > 7) {
+            int ps_extension_id = get_bits(gb, 2);
+            cnt -= 2 + ps_read_extension_data(gb, ps, ps_extension_id);
+        }
+        if (cnt < 0) {
+            av_log(avctx, AV_LOG_ERROR, "ps extension overflow %d\n", cnt);
+            goto err;
+        }
+        skip_bits(gb, cnt);
+    }
+
+    ps->enable_ipdopd &= !PS_BASELINE;
+
+    //Fix up envelopes
+    if (!ps->num_env || ps->border_position[ps->num_env] < numQMFSlots - 1) {
+        //Create a fake envelope
+        int source = ps->num_env ? ps->num_env - 1 : ps->num_env_old - 1;
+        int b;
+        if (source >= 0 && source != ps->num_env) {
+            if (ps->enable_iid) {
+                memcpy(ps->iid_par+ps->num_env, ps->iid_par+source, sizeof(ps->iid_par[0]));
+            }
+            if (ps->enable_icc) {
+                memcpy(ps->icc_par+ps->num_env, ps->icc_par+source, sizeof(ps->icc_par[0]));
+            }
+            if (ps->enable_ipdopd) {
+                memcpy(ps->ipd_par+ps->num_env, ps->ipd_par+source, sizeof(ps->ipd_par[0]));
+                memcpy(ps->opd_par+ps->num_env, ps->opd_par+source, sizeof(ps->opd_par[0]));
+            }
+        }
+        if (ps->enable_iid){
+            for (b = 0; b < ps->nr_iid_par; b++) {
+                if (FFABS(ps->iid_par[ps->num_env][b]) > 7 + 8 * ps->iid_quant) {
+                    av_log(avctx, AV_LOG_ERROR, "iid_par invalid\n");
+                    goto err;
+                }
+            }
+        }
+        if (ps->enable_icc){
+            for (b = 0; b < ps->nr_iid_par; b++) {
+                if (ps->icc_par[ps->num_env][b] > 7U) {
+                    av_log(avctx, AV_LOG_ERROR, "icc_par invalid\n");
+                    goto err;
+                }
+            }
+        }
+        ps->num_env++;
+        ps->border_position[ps->num_env] = numQMFSlots - 1;
+    }
+
+
+    ps->is34bands_old = ps->is34bands;
+    if (!PS_BASELINE && (ps->enable_iid || ps->enable_icc))
+        ps->is34bands = (ps->enable_iid && ps->nr_iid_par == 34) ||
+                        (ps->enable_icc && ps->nr_icc_par == 34);
+
+    //Baseline
+    if (!ps->enable_ipdopd) {
+        memset(ps->ipd_par, 0, sizeof(ps->ipd_par));
+        memset(ps->opd_par, 0, sizeof(ps->opd_par));
+    }
+
+    if (header)
+        ps->start = 1;
+
+    bits_consumed = get_bits_count(gb) - bit_count_start;
+    if (bits_consumed <= bits_left) {
+        skip_bits_long(gb_host, bits_consumed);
+        return bits_consumed;
+    }
+    av_log(avctx, AV_LOG_ERROR, "Expected to read %d PS bits actually read %d.\n", bits_left, bits_consumed);
+err:
+    ps->start = 0;
+    skip_bits_long(gb_host, bits_left);
+    memset(ps->iid_par, 0, sizeof(ps->iid_par));
+    memset(ps->icc_par, 0, sizeof(ps->icc_par));
+    memset(ps->ipd_par, 0, sizeof(ps->ipd_par));
+    memset(ps->opd_par, 0, sizeof(ps->opd_par));
+    return bits_left;
+}
+
+#define PS_INIT_VLC_STATIC(num, size) \
+    INIT_VLC_STATIC(&vlc_ps[num], 9, ps_tmp[num].table_size / ps_tmp[num].elem_size,    \
+                    ps_tmp[num].ps_bits, 1, 1,                                          \
+                    ps_tmp[num].ps_codes, ps_tmp[num].elem_size, ps_tmp[num].elem_size, \
+                    size);
+
+#define PS_VLC_ROW(name) \
+    { name ## _codes, name ## _bits, sizeof(name ## _codes), sizeof(name ## _codes[0]) }
+
+static av_cold void ps_init_common(void)
+{
+    // Syntax initialization
+    static const struct {
+        const void *ps_codes, *ps_bits;
+        const unsigned int table_size, elem_size;
+    } ps_tmp[] = {
+        PS_VLC_ROW(huff_iid_df1),
+        PS_VLC_ROW(huff_iid_dt1),
+        PS_VLC_ROW(huff_iid_df0),
+        PS_VLC_ROW(huff_iid_dt0),
+        PS_VLC_ROW(huff_icc_df),
+        PS_VLC_ROW(huff_icc_dt),
+        PS_VLC_ROW(huff_ipd_df),
+        PS_VLC_ROW(huff_ipd_dt),
+        PS_VLC_ROW(huff_opd_df),
+        PS_VLC_ROW(huff_opd_dt),
+    };
+
+    PS_INIT_VLC_STATIC(0, 1544);
+    PS_INIT_VLC_STATIC(1,  832);
+    PS_INIT_VLC_STATIC(2, 1024);
+    PS_INIT_VLC_STATIC(3, 1036);
+    PS_INIT_VLC_STATIC(4,  544);
+    PS_INIT_VLC_STATIC(5,  544);
+    PS_INIT_VLC_STATIC(6,  512);
+    PS_INIT_VLC_STATIC(7,  512);
+    PS_INIT_VLC_STATIC(8,  512);
+    PS_INIT_VLC_STATIC(9,  512);
+}
+
+av_cold void ff_ps_init_common(void)
+{
+    static AVOnce init_static_once = AV_ONCE_INIT;
+    ff_thread_once(&init_static_once, ps_init_common);
+}