[FFmpeg-devel] [PATCH] avcodec: add ScreenPressor decoder
Paul B Mahol
onemda at gmail.com
Mon Feb 20 22:41:16 EET 2017
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 1 +
libavcodec/avcodec.h | 1 +
libavcodec/codec_desc.c | 7 +
libavcodec/scpr.c | 799 ++++++++++++++++++++++++++++++++++++++++++++++++
libavformat/riff.c | 1 +
6 files changed, 810 insertions(+)
create mode 100644 libavcodec/scpr.c
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index a1ce264..1bea44a 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -509,6 +509,7 @@ OBJS-$(CONFIG_SAMI_DECODER) += samidec.o ass.o htmlsubtitles.o
OBJS-$(CONFIG_S302M_DECODER) += s302m.o
OBJS-$(CONFIG_S302M_ENCODER) += s302menc.o
OBJS-$(CONFIG_SANM_DECODER) += sanm.o
+OBJS-$(CONFIG_SCPR_DECODER) += scpr.o
OBJS-$(CONFIG_SCREENPRESSO_DECODER) += screenpresso.o
OBJS-$(CONFIG_SDX2_DPCM_DECODER) += dpcm.o
OBJS-$(CONFIG_SGI_DECODER) += sgidec.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index f12a54d..eee322b 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -307,6 +307,7 @@ void avcodec_register_all(void)
REGISTER_DECODER(RV40, rv40);
REGISTER_ENCDEC (S302M, s302m);
REGISTER_DECODER(SANM, sanm);
+ REGISTER_DECODER(SCPR, scpr);
REGISTER_DECODER(SCREENPRESSO, screenpresso);
REGISTER_DECODER(SDX2_DPCM, sdx2_dpcm);
REGISTER_ENCDEC (SGI, sgi);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 5616fb0..925a8c7 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -415,6 +415,7 @@ enum AVCodecID {
AV_CODEC_ID_PIXLET,
AV_CODEC_ID_SPEEDHQ,
AV_CODEC_ID_FMVC,
+ AV_CODEC_ID_SCPR,
/* various PCM "codecs" */
AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 35846c0..42935d7 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1360,6 +1360,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
.long_name = NULL_IF_CONFIG_SMALL("FM Screen Capture Codec"),
.props = AV_CODEC_PROP_LOSSLESS,
},
+ {
+ .id = AV_CODEC_ID_SCPR,
+ .type = AVMEDIA_TYPE_VIDEO,
+ .name = "scpr",
+ .long_name = NULL_IF_CONFIG_SMALL("ScreenPressor"),
+ .props = AV_CODEC_PROP_LOSSLESS | AV_CODEC_PROP_LOSSY,
+ },
/* image codecs */
{
diff --git a/libavcodec/scpr.c b/libavcodec/scpr.c
new file mode 100644
index 0000000..e151e3a
--- /dev/null
+++ b/libavcodec/scpr.c
@@ -0,0 +1,799 @@
+/*
+ * ScreenPressor decoder
+ *
+ * Copyright (c) 2017 Paul B Mahol
+ *
+ * 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+
+#define TOP 0x01000000
+#define BOT 0x010000
+
+typedef struct RangeCoder {
+ unsigned code;
+ unsigned range;
+} RangeCoder;
+
+typedef struct SCPRContext {
+ AVFrame *last_frame;
+ AVFrame *current_frame;
+ GetByteContext gb;
+ RangeCoder rc;
+ unsigned cn[3][4096 * 273];
+ unsigned ptype[6][7];
+ unsigned n[6][257];
+ unsigned xx[257];
+ unsigned n2[257];
+ unsigned bt[6];
+ unsigned sxy[4][17];
+ unsigned mv[2][513];
+ unsigned nbx, nby;
+ unsigned nbcount;
+ unsigned *bts;
+ int cxshift;
+} SCPRContext;
+
+static void init_rangecoder(RangeCoder *rc, GetByteContext *gb)
+{
+ rc->code = 0;
+ rc->range = 0xFFFFFFFFU;
+ rc->code = bytestream2_get_be32(gb);
+}
+
+static void reinit_tables(SCPRContext *s)
+{
+ int comp, i, j;
+
+ for (comp = 0; comp < 3; comp++) {
+ for (j = 0; j < 4096; j++) {
+ int p = j * 273;
+ if (s->cn[comp][p + 16] != 256) {
+ for (i = 0; i < 256; i++)
+ s->cn[comp][p + i + 17] = 1;
+ for (i = 0; i < 16; i++)
+ s->cn[comp][p + i] = 16;
+ s->cn[comp][p + 16] = 256;
+ }
+ }
+ }
+
+ for (j = 0; j < 6; j++) {
+ unsigned *p = s->n[j];
+ for (i = 0; i < 256; i++)
+ p[i] = 1;
+ p[256] = 256;
+ }
+
+ for (j = 0; j < 6; j++) {
+ unsigned *op = s->ptype[j];
+ for (i = 0; i < 6; i++)
+ op[i] = 1;
+ op[6] = 6;
+ }
+
+ for (i = 0; i < 256; i++) {
+ s->xx[i] = 1;
+ s->n2[i] = 1;
+ }
+ s->xx[256] = 256;
+ s->n2[256] = 256;
+
+ for (i = 0; i < 5; i++) {
+ s->bt[i] = 1;
+ }
+ s->bt[5] = 5;
+
+ for (j = 0; j < 4; j++) {
+ for (i = 0; i < 16; i++) {
+ s->sxy[j][i] = 1;
+ }
+ s->sxy[j][16] = 16;
+ }
+
+ for (i = 0; i < 512; i++) {
+ s->mv[0][i] = 1;
+ s->mv[1][i] = 1;
+ }
+ s->mv[0][512] = 512;
+ s->mv[1][512] = 512;
+}
+
+static void decode(GetByteContext *gb, RangeCoder *rc, unsigned cumFreq, unsigned freq, unsigned total_freq)
+{
+ rc->code -= cumFreq * rc->range;
+ rc->range *= freq;
+
+ while (rc->range < TOP && bytestream2_get_bytes_left(gb) > 0) {
+ unsigned byte = bytestream2_get_byte(gb);
+ rc->code = (rc->code << 8) | byte;
+ rc->range <<= 8;
+ }
+}
+
+static int get_freq(RangeCoder *rc, unsigned total_freq, unsigned *freq)
+{
+ if (total_freq == 0)
+ return AVERROR_INVALIDDATA;
+
+ rc->range = rc->range / total_freq;
+
+ if (rc->range == 0)
+ return AVERROR_INVALIDDATA;
+
+ *freq = rc->code / rc->range;
+
+ return 0;
+}
+
+static int decode_value(SCPRContext *s, unsigned *cnt, unsigned maxc, unsigned step, unsigned *rval)
+{
+ GetByteContext *gb = &s->gb;
+ RangeCoder *rc = &s->rc;
+ unsigned totfr = cnt[maxc];
+ unsigned value;
+ unsigned c = 0, cumfr = 0, cnt_c = 0;
+ int i, ret;
+
+ if ((ret = get_freq(rc, totfr, &value)) < 0)
+ return ret;
+
+ while (c < maxc) {
+ cnt_c = cnt[c];
+ if (value >= cumfr + cnt_c)
+ cumfr += cnt_c;
+ else
+ break;
+ c++;
+ }
+ decode(gb, rc, cumfr, cnt_c, totfr);
+
+ cnt[c] = cnt_c + step;
+ totfr += step;
+ if (totfr > BOT) {
+ totfr = 0;
+ for (i = 0; i < maxc; i++) {
+ unsigned nc = (cnt[i] >> 1) + 1;
+ cnt[i] = nc;
+ totfr += nc;
+ }
+ }
+
+ cnt[maxc] = totfr;
+ *rval = c;
+
+ return 0;
+}
+
+static int decode_unit(SCPRContext *s, unsigned *cnt, unsigned off, unsigned step, unsigned *rval)
+{
+ GetByteContext *gb = &s->gb;
+ RangeCoder *rc = &s->rc;
+ unsigned totfr = cnt[off + 16];
+ unsigned value, x = 0, cumfr = 0, cnt_x = 0;
+ int i, j, ret, c, cnt_c;
+
+ if ((ret = get_freq(rc, totfr, &value)) < 0)
+ return ret;
+
+ while (x < 16) {
+ cnt_x = cnt[off + x];
+ if (value >= cumfr + cnt_x)
+ cumfr += cnt_x;
+ else
+ break;
+ x++;
+ }
+
+ c = x * 16;
+ cnt_c = 0;
+ while (c < 256) {
+ cnt_c = cnt[off + c + 17];
+ if (value >= cumfr + cnt_c)
+ cumfr += cnt_c;
+ else
+ break;
+ c++;
+ }
+ decode(gb, rc, cumfr, cnt_c, totfr);
+ cnt[off + c + 17] = cnt_c + step;
+ cnt[off + x] = cnt_x + step;
+ totfr += step;
+ if (totfr > BOT) {
+ totfr = 0;
+ for (i = off + 17; i < off + 256 + 17; i++) {
+ unsigned nc = (cnt[i] >> 1) + 1;
+ cnt[i] = nc;
+ totfr += nc;
+ }
+ for (i = 0; i < 16; i++) {
+ unsigned sum = 0;
+ unsigned i16_17 = off + (i << 4) + 17;
+ for (j = 0; j < 16; j++)
+ sum += cnt[i16_17 + j];
+ cnt[off + i] = sum;
+ }
+ }
+ cnt[off + 16] = totfr;
+
+ *rval = c;
+
+ return 0;
+}
+
+static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
+{
+ SCPRContext *s = avctx->priv_data;
+ GetByteContext *gb = &s->gb;
+ int cx = 0, cx1 = 0, k = 0, clr = 0;
+ int n, r, g, b, y = 0, x = 0, ret;
+ const int cxshift = s->cxshift;
+ int lx, ly, off, ptype;
+
+ reinit_tables(s);
+ bytestream2_skip(gb, 2);
+ init_rangecoder(&s->rc, gb);
+
+ while (k < avctx->width + 1) {
+ ret = decode_unit(s, s->cn[0], (cx + cx1) * 273, 400, &r);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = r >> cxshift;
+ ret = decode_unit(s, s->cn[1], (cx + cx1) * 273, 400, &g);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = g >> cxshift;
+ ret = decode_unit(s, s->cn[2], (cx + cx1) * 273, 400, &b);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = b >> cxshift;
+
+ ret = decode_value(s, s->n[0], 256, 400, &n);
+ if (ret < 0)
+ return ret;
+
+ clr = (b << 16) + (g << 8) + r;
+ k += n;
+ while (n-- > 0) {
+ dst[y * linesize + x] = clr;
+ lx = x;
+ ly = y;
+ x++;
+ if (x >= avctx->width) {
+ x = 0;
+ y++;
+ }
+ }
+ }
+ off = -linesize - 1;
+ ptype = 0;
+
+ while (x < avctx->width && y < avctx->height) {
+ ret = decode_value(s, s->ptype[ptype], 6, 1000, &ptype);
+ if (ptype == 0) {
+ ret = decode_unit(s, s->cn[0], (cx + cx1) * 273, 400, &r);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = r >> cxshift;
+ ret = decode_unit(s, s->cn[1], (cx + cx1) * 273, 400, &g);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = g >> cxshift;
+ ret = decode_unit(s, s->cn[2], (cx + cx1) * 273, 400, &b);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = b >> cxshift;
+ clr = (b << 16) + (g << 8) + r;
+ }
+ ret = decode_value(s, s->n[ptype], 256, 400, &n);
+ if (ret < 0)
+ return ret;
+
+ switch (ptype) {
+ case 0:
+ while (n-- > 0) {
+ dst[y * linesize + x] = clr;
+ lx = x;
+ ly = y;
+ x++;
+ if (x >= avctx->width) {
+ x = 0;
+ y++;
+ }
+ }
+ break;
+ case 1:
+ while (n-- > 0) {
+ dst[y * linesize + x] = dst[ly * linesize + lx];
+ lx = x;
+ ly = y;
+ x++;
+ if (x >= avctx->width) {
+ x = 0;
+ y++;
+ }
+ }
+ clr = dst[ly * linesize + lx];
+ break;
+ case 2:
+ while (n-- > 0) {
+ clr = dst[y * linesize + x + off + 1];
+ dst[y * linesize + x] = clr;
+ lx = x;
+ ly = y;
+ x++;
+ if (x >= avctx->width) {
+ x = 0;
+ y++;
+ }
+ }
+ break;
+ case 4:
+ while (n-- > 0) {
+ uint8_t *odst = (uint8_t *)dst;
+ r = odst[(ly * linesize + lx) * 4 ] + odst[((y * linesize + x) + off) * 4 + 4] - odst[((y * linesize + x) + off) * 4 ];
+ g = odst[(ly * linesize + lx) * 4 + 1] + odst[((y * linesize + x) + off) * 4 + 5] - odst[((y * linesize + x) + off) * 4 + 1];
+ b = odst[(ly * linesize + lx) * 4 + 2] + odst[((y * linesize + x) + off) * 4 + 6] - odst[((y * linesize + x) + off) * 4 + 2];
+ clr = ((b & 0xFF) << 16) + ((g & 0xFF) << 8) + (r & 0xFF);
+ dst[y * linesize + x] = clr;
+ lx = x;
+ ly = y;
+ x++;
+ if (x >= avctx->width) {
+ x = 0;
+ y++;
+ }
+ }
+ break;
+ case 5:
+ while (n-- > 0) {
+ clr = dst[y * linesize + x + off];
+ dst[y * linesize + x] = clr;
+ lx = x;
+ ly = y;
+ x++;
+ if (x >= avctx->width) {
+ x = 0;
+ y++;
+ }
+ }
+ break;
+ }
+
+ if (avctx->bits_per_coded_sample == 16) {
+ cx1 = (clr & 0xFF00) >> 2;
+ cx = (clr & 0xFFFFFF) >> 16;
+ } else {
+ cx1 = (clr & 0xFC00) >> 4;
+ cx = (clr & 0xFFFFFF) >> 18;
+ }
+ }
+
+ return 0;
+}
+
+static int decompress_p(AVCodecContext *avctx,
+ uint32_t *dst, int linesize,
+ uint32_t *prev, int plinesize)
+{
+ SCPRContext *s = avctx->priv_data;
+ GetByteContext *gb = &s->gb;
+ int ret, temp, min, max, x, y, cx = 0, cx1 = 0;
+ int backstep = linesize - avctx->width;
+ const int cxshift = s->cxshift;
+
+ if (bytestream2_get_byte(gb) == 0)
+ return 0;
+ bytestream2_skip(gb, 1);
+ init_rangecoder(&s->rc, gb);
+
+ ret = decode_value(s, s->xx, 256, 1, &min);
+ ret |= decode_value(s, s->xx, 256, 1, &temp);
+ min += temp << 8;
+ ret |= decode_value(s, s->xx, 256, 1, &max);
+ ret |= decode_value(s, s->xx, 256, 1, &temp);
+ if (ret < 0)
+ return ret;
+
+ max += temp << 8;
+ memset(s->bts, 0, sizeof(*s->bts) * s->nbcount);
+
+ while (min <= max) {
+ int fill, count;
+
+ ret = decode_value(s, s->bt, 5, 10, &fill);
+ ret |= decode_value(s, s->n2, 256, 20, &count);
+ if (ret < 0)
+ return ret;
+
+ while (min < s->nbcount && count-- > 0) {
+ s->bts[min++] = fill;
+ }
+ }
+
+ for (y = 0; y < s->nby; y++) {
+ for (x = 0; x < s->nbx; x++) {
+ int sy1 = 0, sy2 = 16, sx1 = 0, sx2 = 16;
+
+ if (s->bts[y * s->nbx + x] == 0)
+ continue;
+
+ if (((s->bts[y * s->nbx + x] - 1) & 1) > 0) {
+ ret = decode_value(s, s->sxy[0], 16, 100, &sx1);
+ ret |= decode_value(s, s->sxy[1], 16, 100, &sy1);
+ ret |= decode_value(s, s->sxy[2], 16, 100, &sx2);
+ ret |= decode_value(s, s->sxy[3], 16, 100, &sy2);
+ if (ret < 0)
+ return ret;
+
+ sx2++;
+ sy2++;
+ }
+ if (((s->bts[y * s->nbx + x] - 1) & 2) > 0) {
+ int i, j, by = y * 16, bx = x * 16;
+ int mvx, mvy;
+
+ ret = decode_value(s, s->mv[0], 512, 100, &mvx);
+ ret |= decode_value(s, s->mv[1], 512, 100, &mvy);
+ if (ret < 0)
+ return ret;
+
+ mvx -= 256;
+ mvy -= 256;
+
+ if (by + mvy + sy1 < 0 || bx + mvx + sx1 < 0)
+ return AVERROR_INVALIDDATA;
+
+ for (i = 0; i < sy2 - sy1 && (by + sy1 + i) < avctx->height; i++) {
+ for (j = 0; j < sx2 - sx1 && (bx + sx1 + j) < avctx->width; j++) {
+ dst[(by + i + sy1) * linesize + bx + sx1 + j] = prev[(by + mvy + sy1 + i) * plinesize + bx + sx1 + mvx + j];
+ }
+ }
+ } else {
+ int n, r, g, b, z, bx = x * 16 + sx1, by = y * 16 + sy1;
+ unsigned clr, ptype = 0;
+
+ for (; by < y * 16 + sy2 && by < avctx->height;) {
+ ret = decode_value(s, s->ptype[ptype], 6, 1000, &ptype);
+ if (ptype == 0) {
+ ret = decode_unit(s, s->cn[0], (cx + cx1) * 273, 400, &r);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = r >> cxshift;
+ ret = decode_unit(s, s->cn[1], (cx + cx1) * 273, 400, &g);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = g >> cxshift;
+ ret = decode_unit(s, s->cn[2], (cx + cx1) * 273, 400, &b);
+ if (ret < 0)
+ return ret;
+
+ cx1 = (cx << 6) & 0xFC0;
+ cx = b >> cxshift;
+ clr = (b << 16) + (g << 8) + r;
+ }
+ if (ptype > 5)
+ return AVERROR_INVALIDDATA;
+ ret = decode_value(s, s->n[ptype], 256, 400, &n);
+ if (ret < 0)
+ return ret;
+
+ switch (ptype) {
+ case 0:
+ while (n-- > 0) {
+ if (by >= avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ dst[by * linesize + bx] = clr;
+ bx++;
+ if (bx >= x * 16 + sx2 || bx >= avctx->width) {
+ bx = x * 16 + sx1;
+ by++;
+ }
+ }
+ break;
+ case 1:
+ while (n-- > 0) {
+ if (bx == 0) {
+ if (by < 1)
+ return AVERROR_INVALIDDATA;
+ z = backstep;
+ } else {
+ z = 0;
+ }
+
+ if (by >= avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ clr = dst[by * linesize + bx - 1 - z];
+ dst[by * linesize + bx] = clr;
+ bx++;
+ if (bx >= x * 16 + sx2 || bx >= avctx->width) {
+ bx = x * 16 + sx1;
+ by++;
+ }
+ }
+ break;
+ case 2:
+ while (n-- > 0) {
+ if (by < 1 || by >= avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ clr = dst[(by - 1) * linesize + bx];
+ dst[by * linesize + bx] = clr;
+ bx++;
+ if (bx >= x * 16 + sx2 || bx >= avctx->width) {
+ bx = x * 16 + sx1;
+ by++;
+ }
+ }
+ break;
+ case 3:
+ while (n-- > 0) {
+ if (by >= avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ clr = prev[by * linesize + bx];
+ dst[by * linesize + bx] = clr;
+ bx++;
+ if (bx >= x * 16 + sx2 || bx >= avctx->width) {
+ bx = x * 16 + sx1;
+ by++;
+ }
+ }
+ break;
+ case 4:
+ while (n-- > 0) {
+ uint8_t *odst = (uint8_t *)dst;
+
+ if (by < 1 || by >= avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ if (bx == 0) {
+ z = backstep;
+ } else {
+ z = 0;
+ }
+
+ r = odst[((by - 1) * linesize + bx) * 4] +
+ odst[(by * linesize + bx - 1 - z) * 4] -
+ odst[((by - 1) * linesize + bx - 1 - z) * 4];
+ g = odst[((by - 1) * linesize + bx) * 4 + 1] +
+ odst[(by * linesize + bx - 1 - z) * 4 + 1] -
+ odst[((by - 1) * linesize + bx - 1 - z) * 4 + 1];
+ b = odst[((by - 1) * linesize + bx) * 4 + 2] +
+ odst[(by * linesize + bx - 1 - z) * 4 + 2] -
+ odst[((by - 1) * linesize + bx - 1 - z) * 4 + 2];
+ clr = ((b & 0xFF) << 16) + ((g & 0xFF) << 8) + (r & 0xFF);
+ dst[by * linesize + bx] = clr;
+ bx++;
+ if (bx >= x * 16 + sx2 || bx >= avctx->width) {
+ bx = x * 16 + sx1;
+ by++;
+ }
+ }
+ break;
+ case 5:
+ while (n-- > 0) {
+ if (by < 1 || by >= avctx->height)
+ return AVERROR_INVALIDDATA;
+
+ if (bx == 0) {
+ z = backstep;
+ } else {
+ z = 0;
+ }
+
+ clr = dst[(by - 1) * linesize + bx - 1 - z];
+ dst[by * linesize + bx] = clr;
+ bx++;
+ if (bx >= x * 16 + sx2 || bx >= avctx->width) {
+ bx = x * 16 + sx1;
+ by++;
+ }
+ }
+ break;
+ }
+
+ if (avctx->bits_per_coded_sample == 16) {
+ cx1 = (clr & 0xFF00) >> 2;
+ cx = (clr & 0xFFFFFF) >> 16;
+ } else {
+ cx1 = (clr & 0xFC00) >> 4;
+ cx = (clr & 0xFFFFFF) >> 18;
+ }
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
+ AVPacket *avpkt)
+{
+ SCPRContext *s = avctx->priv_data;
+ GetByteContext *gb = &s->gb;
+ AVFrame *frame = data;
+ int ret, type;
+
+ if (avctx->bits_per_coded_sample == 16) {
+ if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+ return ret;
+ }
+
+ if ((ret = ff_reget_buffer(avctx, s->current_frame)) < 0)
+ return ret;
+
+ bytestream2_init(gb, avpkt->data, avpkt->size);
+
+ type = bytestream2_peek_byte(gb);
+
+ if (type == 18) {
+ frame->key_frame = 1;
+ ret = decompress_i(avctx, (uint32_t *)s->current_frame->data[0],
+ s->current_frame->linesize[0] / 4);
+ } else if (type == 17) {
+ uint32_t clr, *dst = (uint32_t *)s->current_frame->data[0];
+ int x, y;
+
+ frame->key_frame = 1;
+ bytestream2_skip(gb, 1);
+ if (avctx->bits_per_coded_sample == 16) {
+ uint16_t value = bytestream2_get_le16(gb);
+ int r, g, b;
+
+ r = (value ) & 31;
+ g = (value >> 5) & 31;
+ b = (value >> 10) & 31;
+ clr = (r << 16) + (g << 8) + b;
+ } else {
+ clr = bytestream2_get_le24(gb);
+ }
+ for (y = 0; y < avctx->height; y++) {
+ for (x = 0; x < avctx->width; x++) {
+ dst[x] = clr;
+ }
+ dst += s->current_frame->linesize[0] / 4;
+ }
+ } else if (type == 0 || type == 1) {
+ frame->key_frame = 0;
+
+ ret = av_frame_copy(s->current_frame, s->last_frame);
+ if (ret < 0)
+ return ret;
+
+ ret = decompress_p(avctx, (uint32_t *)s->current_frame->data[0],
+ s->current_frame->linesize[0] / 4,
+ (uint32_t *)s->last_frame->data[0],
+ s->last_frame->linesize[0] / 4);
+ } else {
+ return AVERROR_PATCHWELCOME;
+ }
+
+ if (ret < 0)
+ return ret;
+
+ if (avctx->bits_per_coded_sample != 16) {
+ ret = av_frame_ref(data, s->current_frame);
+ if (ret < 0)
+ return ret;
+ } else {
+ uint8_t *dst = frame->data[0];
+ int x, y;
+
+ ret = av_frame_copy(frame, s->current_frame);
+ if (ret < 0)
+ return ret;
+
+ for (y = 0; y < avctx->height; y++) {
+ for (x = 0; x < avctx->width * 4; x++) {
+ dst[x] = dst[x] << 3;
+ }
+ dst += frame->linesize[0];
+ }
+ }
+
+ frame->pict_type = frame->key_frame ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
+
+ FFSWAP(AVFrame *, s->current_frame, s->last_frame);
+
+ frame->data[0] += frame->linesize[0] * (avctx->height - 1);
+ frame->linesize[0] *= -1;
+
+ *got_frame = 1;
+
+ return avpkt->size;
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ SCPRContext *s = avctx->priv_data;
+
+ switch (avctx->bits_per_coded_sample) {
+ case 16: avctx->pix_fmt = AV_PIX_FMT_RGB0; break;
+ case 24:
+ case 32: avctx->pix_fmt = AV_PIX_FMT_BGR0; break;
+ default:
+ av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
+ return AVERROR_INVALIDDATA;
+ }
+
+ s->cxshift = avctx->bits_per_coded_sample == 16 ? 0 : 2;
+ s->nbx = (avctx->width + 15) / 16;
+ s->nby = (avctx->height + 15) / 16;
+ s->nbcount = s->nbx * s->nby;
+ s->bts = av_malloc_array(s->nbcount, sizeof(*s->bts));
+ if (!s->bts)
+ return AVERROR(ENOMEM);
+
+ s->last_frame = av_frame_alloc();
+ s->current_frame = av_frame_alloc();
+ if (!s->last_frame || !s->current_frame)
+ return AVERROR(ENOMEM);
+
+ return 0;
+}
+
+static av_cold int decode_close(AVCodecContext *avctx)
+{
+ SCPRContext *s = avctx->priv_data;
+
+ av_freep(&s->bts);
+ av_frame_free(&s->last_frame);
+ av_frame_free(&s->current_frame);
+
+ return 0;
+}
+
+AVCodec ff_scpr_decoder = {
+ .name = "scpr",
+ .long_name = NULL_IF_CONFIG_SMALL("ScreenPressor"),
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_SCPR,
+ .priv_data_size = sizeof(SCPRContext),
+ .init = decode_init,
+ .close = decode_close,
+ .decode = decode_frame,
+ .capabilities = AV_CODEC_CAP_DR1,
+ .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
+ FF_CODEC_CAP_INIT_CLEANUP,
+};
diff --git a/libavformat/riff.c b/libavformat/riff.c
index 7be50c3..e38c636 100644
--- a/libavformat/riff.c
+++ b/libavformat/riff.c
@@ -449,6 +449,7 @@ const AVCodecTag ff_codec_bmp_tags[] = {
{ AV_CODEC_ID_SPEEDHQ, MKTAG('S', 'H', 'Q', '7') },
{ AV_CODEC_ID_SPEEDHQ, MKTAG('S', 'H', 'Q', '9') },
{ AV_CODEC_ID_FMVC, MKTAG('F', 'M', 'V', 'C') },
+ { AV_CODEC_ID_SCPR, MKTAG('S', 'C', 'P', 'R') },
{ AV_CODEC_ID_NONE, 0 }
};
--
2.9.3
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