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authortrav90 <travawine@palemoon.org>2018-10-19 21:52:15 -0500
committertrav90 <travawine@palemoon.org>2018-10-19 21:52:20 -0500
commitbbcc64772580c8a979288791afa02d30bc476d2e (patch)
tree437ce94c3fdd7497508e5b55de06c6d011678597 /third_party/aom/common/y4minput.c
parent14805f6ddbfb173c327768fff9f81f40ce5e81b0 (diff)
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Update aom to v1.0.0
Update aom to commit id d14c5bb4f336ef1842046089849dee4a301fbbf0.
Diffstat (limited to 'third_party/aom/common/y4minput.c')
-rw-r--r--third_party/aom/common/y4minput.c1142
1 files changed, 1142 insertions, 0 deletions
diff --git a/third_party/aom/common/y4minput.c b/third_party/aom/common/y4minput.c
new file mode 100644
index 000000000..a1dca10cd
--- /dev/null
+++ b/third_party/aom/common/y4minput.c
@@ -0,0 +1,1142 @@
+/*
+ * Copyright (c) 2016, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+ *
+ * Based on code from the OggTheora software codec source code,
+ * Copyright (C) 2002-2010 The Xiph.Org Foundation and contributors.
+ */
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "aom/aom_integer.h"
+#include "y4minput.h"
+
+// Reads 'size' bytes from 'file' into 'buf' with some fault tolerance.
+// Returns true on success.
+static int file_read(void *buf, size_t size, FILE *file) {
+ const int kMaxRetries = 5;
+ int retry_count = 0;
+ int file_error;
+ size_t len = 0;
+ do {
+ const size_t n = fread((uint8_t *)buf + len, 1, size - len, file);
+ len += n;
+ file_error = ferror(file);
+ if (file_error) {
+ if (errno == EINTR || errno == EAGAIN) {
+ clearerr(file);
+ continue;
+ } else {
+ fprintf(stderr, "Error reading file: %u of %u bytes read, %d: %s\n",
+ (uint32_t)len, (uint32_t)size, errno, strerror(errno));
+ return 0;
+ }
+ }
+ } while (!feof(file) && len < size && ++retry_count < kMaxRetries);
+
+ if (!feof(file) && len != size) {
+ fprintf(stderr,
+ "Error reading file: %u of %u bytes read,"
+ " error: %d, retries: %d, %d: %s\n",
+ (uint32_t)len, (uint32_t)size, file_error, retry_count, errno,
+ strerror(errno));
+ }
+ return len == size;
+}
+
+static int y4m_parse_tags(y4m_input *_y4m, char *_tags) {
+ int got_w;
+ int got_h;
+ int got_fps;
+ int got_interlace;
+ int got_par;
+ int got_chroma;
+ char *p;
+ char *q;
+ got_w = got_h = got_fps = got_interlace = got_par = got_chroma = 0;
+ for (p = _tags;; p = q) {
+ /*Skip any leading spaces.*/
+ while (*p == ' ') p++;
+ /*If that's all we have, stop.*/
+ if (p[0] == '\0') break;
+ /*Find the end of this tag.*/
+ for (q = p + 1; *q != '\0' && *q != ' '; q++) {
+ }
+ /*Process the tag.*/
+ switch (p[0]) {
+ case 'W': {
+ if (sscanf(p + 1, "%d", &_y4m->pic_w) != 1) return -1;
+ got_w = 1;
+ } break;
+ case 'H': {
+ if (sscanf(p + 1, "%d", &_y4m->pic_h) != 1) return -1;
+ got_h = 1;
+ } break;
+ case 'F': {
+ if (sscanf(p + 1, "%d:%d", &_y4m->fps_n, &_y4m->fps_d) != 2) {
+ return -1;
+ }
+ got_fps = 1;
+ } break;
+ case 'I': {
+ _y4m->interlace = p[1];
+ got_interlace = 1;
+ } break;
+ case 'A': {
+ if (sscanf(p + 1, "%d:%d", &_y4m->par_n, &_y4m->par_d) != 2) {
+ return -1;
+ }
+ got_par = 1;
+ } break;
+ case 'C': {
+ if (q - p > 16) return -1;
+ memcpy(_y4m->chroma_type, p + 1, q - p - 1);
+ _y4m->chroma_type[q - p - 1] = '\0';
+ got_chroma = 1;
+ } break;
+ /*Ignore unknown tags.*/
+ }
+ }
+ if (!got_w || !got_h || !got_fps) return -1;
+ if (!got_interlace) _y4m->interlace = '?';
+ if (!got_par) _y4m->par_n = _y4m->par_d = 0;
+ /*Chroma-type is not specified in older files, e.g., those generated by
+ mplayer.*/
+ if (!got_chroma) strcpy(_y4m->chroma_type, "420");
+ return 0;
+}
+
+/*All anti-aliasing filters in the following conversion functions are based on
+ one of two window functions:
+ The 6-tap Lanczos window (for down-sampling and shifts):
+ sinc(\pi*t)*sinc(\pi*t/3), |t|<3 (sinc(t)==sin(t)/t)
+ 0, |t|>=3
+ The 4-tap Mitchell window (for up-sampling):
+ 7|t|^3-12|t|^2+16/3, |t|<1
+ -(7/3)|x|^3+12|x|^2-20|x|+32/3, |t|<2
+ 0, |t|>=2
+ The number of taps is intentionally kept small to reduce computational
+ overhead and limit ringing.
+
+ The taps from these filters are scaled so that their sum is 1, and the
+ result is scaled by 128 and rounded to integers to create a filter whose
+ intermediate values fit inside 16 bits.
+ Coefficients are rounded in such a way as to ensure their sum is still 128,
+ which is usually equivalent to normal rounding.
+
+ Conversions which require both horizontal and vertical filtering could
+ have these steps pipelined, for less memory consumption and better cache
+ performance, but we do them separately for simplicity.*/
+#define OC_MINI(_a, _b) ((_a) > (_b) ? (_b) : (_a))
+#define OC_MAXI(_a, _b) ((_a) < (_b) ? (_b) : (_a))
+#define OC_CLAMPI(_a, _b, _c) (OC_MAXI(_a, OC_MINI(_b, _c)))
+
+/*420jpeg chroma samples are sited like:
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ 420mpeg2 chroma samples are sited like:
+ Y-------Y-------Y-------Y-------
+ | | | |
+ BR | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ BR | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ We use a resampling filter to shift the site locations one quarter pixel (at
+ the chroma plane's resolution) to the right.
+ The 4:2:2 modes look exactly the same, except there are twice as many chroma
+ lines, and they are vertically co-sited with the luma samples in both the
+ mpeg2 and jpeg cases (thus requiring no vertical resampling).*/
+static void y4m_42xmpeg2_42xjpeg_helper(unsigned char *_dst,
+ const unsigned char *_src, int _c_w,
+ int _c_h) {
+ int y;
+ int x;
+ for (y = 0; y < _c_h; y++) {
+ /*Filter: [4 -17 114 35 -9 1]/128, derived from a 6-tap Lanczos
+ window.*/
+ for (x = 0; x < OC_MINI(_c_w, 2); x++) {
+ _dst[x] = (unsigned char)OC_CLAMPI(
+ 0,
+ (4 * _src[0] - 17 * _src[OC_MAXI(x - 1, 0)] + 114 * _src[x] +
+ 35 * _src[OC_MINI(x + 1, _c_w - 1)] -
+ 9 * _src[OC_MINI(x + 2, _c_w - 1)] + _src[OC_MINI(x + 3, _c_w - 1)] +
+ 64) >>
+ 7,
+ 255);
+ }
+ for (; x < _c_w - 3; x++) {
+ _dst[x] = (unsigned char)OC_CLAMPI(
+ 0,
+ (4 * _src[x - 2] - 17 * _src[x - 1] + 114 * _src[x] +
+ 35 * _src[x + 1] - 9 * _src[x + 2] + _src[x + 3] + 64) >>
+ 7,
+ 255);
+ }
+ for (; x < _c_w; x++) {
+ _dst[x] = (unsigned char)OC_CLAMPI(
+ 0,
+ (4 * _src[x - 2] - 17 * _src[x - 1] + 114 * _src[x] +
+ 35 * _src[OC_MINI(x + 1, _c_w - 1)] -
+ 9 * _src[OC_MINI(x + 2, _c_w - 1)] + _src[_c_w - 1] + 64) >>
+ 7,
+ 255);
+ }
+ _dst += _c_w;
+ _src += _c_w;
+ }
+}
+
+/*Handles both 422 and 420mpeg2 to 422jpeg and 420jpeg, respectively.*/
+static void y4m_convert_42xmpeg2_42xjpeg(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ int c_w;
+ int c_h;
+ int c_sz;
+ int pli;
+ /*Skip past the luma data.*/
+ _dst += _y4m->pic_w * _y4m->pic_h;
+ /*Compute the size of each chroma plane.*/
+ c_w = (_y4m->pic_w + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h;
+ c_h = (_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v;
+ c_sz = c_w * c_h;
+ for (pli = 1; pli < 3; pli++) {
+ y4m_42xmpeg2_42xjpeg_helper(_dst, _aux, c_w, c_h);
+ _dst += c_sz;
+ _aux += c_sz;
+ }
+}
+
+/*This format is only used for interlaced content, but is included for
+ completeness.
+
+ 420jpeg chroma samples are sited like:
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ 420paldv chroma samples are sited like:
+ YR------Y-------YR------Y-------
+ | | | |
+ | | | |
+ | | | |
+ YB------Y-------YB------Y-------
+ | | | |
+ | | | |
+ | | | |
+ YR------Y-------YR------Y-------
+ | | | |
+ | | | |
+ | | | |
+ YB------Y-------YB------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ We use a resampling filter to shift the site locations one quarter pixel (at
+ the chroma plane's resolution) to the right.
+ Then we use another filter to move the C_r location down one quarter pixel,
+ and the C_b location up one quarter pixel.*/
+static void y4m_convert_42xpaldv_42xjpeg(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ unsigned char *tmp;
+ int c_w;
+ int c_h;
+ int c_sz;
+ int pli;
+ int y;
+ int x;
+ /*Skip past the luma data.*/
+ _dst += _y4m->pic_w * _y4m->pic_h;
+ /*Compute the size of each chroma plane.*/
+ c_w = (_y4m->pic_w + 1) / 2;
+ c_h = (_y4m->pic_h + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h;
+ c_sz = c_w * c_h;
+ tmp = _aux + 2 * c_sz;
+ for (pli = 1; pli < 3; pli++) {
+ /*First do the horizontal re-sampling.
+ This is the same as the mpeg2 case, except that after the horizontal
+ case, we need to apply a second vertical filter.*/
+ y4m_42xmpeg2_42xjpeg_helper(tmp, _aux, c_w, c_h);
+ _aux += c_sz;
+ switch (pli) {
+ case 1: {
+ /*Slide C_b up a quarter-pel.
+ This is the same filter used above, but in the other order.*/
+ for (x = 0; x < c_w; x++) {
+ for (y = 0; y < OC_MINI(c_h, 3); y++) {
+ _dst[y * c_w] = (unsigned char)OC_CLAMPI(
+ 0,
+ (tmp[0] - 9 * tmp[OC_MAXI(y - 2, 0) * c_w] +
+ 35 * tmp[OC_MAXI(y - 1, 0) * c_w] + 114 * tmp[y * c_w] -
+ 17 * tmp[OC_MINI(y + 1, c_h - 1) * c_w] +
+ 4 * tmp[OC_MINI(y + 2, c_h - 1) * c_w] + 64) >>
+ 7,
+ 255);
+ }
+ for (; y < c_h - 2; y++) {
+ _dst[y * c_w] = (unsigned char)OC_CLAMPI(
+ 0,
+ (tmp[(y - 3) * c_w] - 9 * tmp[(y - 2) * c_w] +
+ 35 * tmp[(y - 1) * c_w] + 114 * tmp[y * c_w] -
+ 17 * tmp[(y + 1) * c_w] + 4 * tmp[(y + 2) * c_w] + 64) >>
+ 7,
+ 255);
+ }
+ for (; y < c_h; y++) {
+ _dst[y * c_w] = (unsigned char)OC_CLAMPI(
+ 0,
+ (tmp[(y - 3) * c_w] - 9 * tmp[(y - 2) * c_w] +
+ 35 * tmp[(y - 1) * c_w] + 114 * tmp[y * c_w] -
+ 17 * tmp[OC_MINI(y + 1, c_h - 1) * c_w] +
+ 4 * tmp[(c_h - 1) * c_w] + 64) >>
+ 7,
+ 255);
+ }
+ _dst++;
+ tmp++;
+ }
+ _dst += c_sz - c_w;
+ tmp -= c_w;
+ } break;
+ case 2: {
+ /*Slide C_r down a quarter-pel.
+ This is the same as the horizontal filter.*/
+ for (x = 0; x < c_w; x++) {
+ for (y = 0; y < OC_MINI(c_h, 2); y++) {
+ _dst[y * c_w] = (unsigned char)OC_CLAMPI(
+ 0,
+ (4 * tmp[0] - 17 * tmp[OC_MAXI(y - 1, 0) * c_w] +
+ 114 * tmp[y * c_w] + 35 * tmp[OC_MINI(y + 1, c_h - 1) * c_w] -
+ 9 * tmp[OC_MINI(y + 2, c_h - 1) * c_w] +
+ tmp[OC_MINI(y + 3, c_h - 1) * c_w] + 64) >>
+ 7,
+ 255);
+ }
+ for (; y < c_h - 3; y++) {
+ _dst[y * c_w] = (unsigned char)OC_CLAMPI(
+ 0,
+ (4 * tmp[(y - 2) * c_w] - 17 * tmp[(y - 1) * c_w] +
+ 114 * tmp[y * c_w] + 35 * tmp[(y + 1) * c_w] -
+ 9 * tmp[(y + 2) * c_w] + tmp[(y + 3) * c_w] + 64) >>
+ 7,
+ 255);
+ }
+ for (; y < c_h; y++) {
+ _dst[y * c_w] = (unsigned char)OC_CLAMPI(
+ 0,
+ (4 * tmp[(y - 2) * c_w] - 17 * tmp[(y - 1) * c_w] +
+ 114 * tmp[y * c_w] + 35 * tmp[OC_MINI(y + 1, c_h - 1) * c_w] -
+ 9 * tmp[OC_MINI(y + 2, c_h - 1) * c_w] + tmp[(c_h - 1) * c_w] +
+ 64) >>
+ 7,
+ 255);
+ }
+ _dst++;
+ tmp++;
+ }
+ } break;
+ }
+ /*For actual interlaced material, this would have to be done separately on
+ each field, and the shift amounts would be different.
+ C_r moves down 1/8, C_b up 3/8 in the top field, and C_r moves down 3/8,
+ C_b up 1/8 in the bottom field.
+ The corresponding filters would be:
+ Down 1/8 (reverse order for up): [3 -11 125 15 -4 0]/128
+ Down 3/8 (reverse order for up): [4 -19 98 56 -13 2]/128*/
+ }
+}
+
+/*Perform vertical filtering to reduce a single plane from 4:2:2 to 4:2:0.
+ This is used as a helper by several converation routines.*/
+static void y4m_422jpeg_420jpeg_helper(unsigned char *_dst,
+ const unsigned char *_src, int _c_w,
+ int _c_h) {
+ int y;
+ int x;
+ /*Filter: [3 -17 78 78 -17 3]/128, derived from a 6-tap Lanczos window.*/
+ for (x = 0; x < _c_w; x++) {
+ for (y = 0; y < OC_MINI(_c_h, 2); y += 2) {
+ _dst[(y >> 1) * _c_w] =
+ OC_CLAMPI(0,
+ (64 * _src[0] + 78 * _src[OC_MINI(1, _c_h - 1) * _c_w] -
+ 17 * _src[OC_MINI(2, _c_h - 1) * _c_w] +
+ 3 * _src[OC_MINI(3, _c_h - 1) * _c_w] + 64) >>
+ 7,
+ 255);
+ }
+ for (; y < _c_h - 3; y += 2) {
+ _dst[(y >> 1) * _c_w] =
+ OC_CLAMPI(0,
+ (3 * (_src[(y - 2) * _c_w] + _src[(y + 3) * _c_w]) -
+ 17 * (_src[(y - 1) * _c_w] + _src[(y + 2) * _c_w]) +
+ 78 * (_src[y * _c_w] + _src[(y + 1) * _c_w]) + 64) >>
+ 7,
+ 255);
+ }
+ for (; y < _c_h; y += 2) {
+ _dst[(y >> 1) * _c_w] = OC_CLAMPI(
+ 0,
+ (3 * (_src[(y - 2) * _c_w] + _src[(_c_h - 1) * _c_w]) -
+ 17 * (_src[(y - 1) * _c_w] + _src[OC_MINI(y + 2, _c_h - 1) * _c_w]) +
+ 78 * (_src[y * _c_w] + _src[OC_MINI(y + 1, _c_h - 1) * _c_w]) +
+ 64) >>
+ 7,
+ 255);
+ }
+ _src++;
+ _dst++;
+ }
+}
+
+/*420jpeg chroma samples are sited like:
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ 422jpeg chroma samples are sited like:
+ Y---BR--Y-------Y---BR--Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y---BR--Y-------Y---BR--Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y---BR--Y-------Y---BR--Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y---BR--Y-------Y---BR--Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ We use a resampling filter to decimate the chroma planes by two in the
+ vertical direction.*/
+static void y4m_convert_422jpeg_420jpeg(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ int c_w;
+ int c_h;
+ int c_sz;
+ int dst_c_w;
+ int dst_c_h;
+ int dst_c_sz;
+ int pli;
+ /*Skip past the luma data.*/
+ _dst += _y4m->pic_w * _y4m->pic_h;
+ /*Compute the size of each chroma plane.*/
+ c_w = (_y4m->pic_w + _y4m->src_c_dec_h - 1) / _y4m->src_c_dec_h;
+ c_h = _y4m->pic_h;
+ dst_c_w = (_y4m->pic_w + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h;
+ dst_c_h = (_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v;
+ c_sz = c_w * c_h;
+ dst_c_sz = dst_c_w * dst_c_h;
+ for (pli = 1; pli < 3; pli++) {
+ y4m_422jpeg_420jpeg_helper(_dst, _aux, c_w, c_h);
+ _aux += c_sz;
+ _dst += dst_c_sz;
+ }
+}
+
+/*420jpeg chroma samples are sited like:
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ 422 chroma samples are sited like:
+ YBR-----Y-------YBR-----Y-------
+ | | | |
+ | | | |
+ | | | |
+ YBR-----Y-------YBR-----Y-------
+ | | | |
+ | | | |
+ | | | |
+ YBR-----Y-------YBR-----Y-------
+ | | | |
+ | | | |
+ | | | |
+ YBR-----Y-------YBR-----Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ We use a resampling filter to shift the original site locations one quarter
+ pixel (at the original chroma resolution) to the right.
+ Then we use a second resampling filter to decimate the chroma planes by two
+ in the vertical direction.*/
+static void y4m_convert_422_420jpeg(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ unsigned char *tmp;
+ int c_w;
+ int c_h;
+ int c_sz;
+ int dst_c_h;
+ int dst_c_sz;
+ int pli;
+ /*Skip past the luma data.*/
+ _dst += _y4m->pic_w * _y4m->pic_h;
+ /*Compute the size of each chroma plane.*/
+ c_w = (_y4m->pic_w + _y4m->src_c_dec_h - 1) / _y4m->src_c_dec_h;
+ c_h = _y4m->pic_h;
+ dst_c_h = (_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v;
+ c_sz = c_w * c_h;
+ dst_c_sz = c_w * dst_c_h;
+ tmp = _aux + 2 * c_sz;
+ for (pli = 1; pli < 3; pli++) {
+ /*In reality, the horizontal and vertical steps could be pipelined, for
+ less memory consumption and better cache performance, but we do them
+ separately for simplicity.*/
+ /*First do horizontal filtering (convert to 422jpeg)*/
+ y4m_42xmpeg2_42xjpeg_helper(tmp, _aux, c_w, c_h);
+ /*Now do the vertical filtering.*/
+ y4m_422jpeg_420jpeg_helper(_dst, tmp, c_w, c_h);
+ _aux += c_sz;
+ _dst += dst_c_sz;
+ }
+}
+
+/*420jpeg chroma samples are sited like:
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | BR | | BR |
+ | | | |
+ Y-------Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ 411 chroma samples are sited like:
+ YBR-----Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ YBR-----Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ YBR-----Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+ YBR-----Y-------Y-------Y-------
+ | | | |
+ | | | |
+ | | | |
+
+ We use a filter to resample at site locations one eighth pixel (at the source
+ chroma plane's horizontal resolution) and five eighths of a pixel to the
+ right.
+ Then we use another filter to decimate the planes by 2 in the vertical
+ direction.*/
+static void y4m_convert_411_420jpeg(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ unsigned char *tmp;
+ int c_w;
+ int c_h;
+ int c_sz;
+ int dst_c_w;
+ int dst_c_h;
+ int dst_c_sz;
+ int tmp_sz;
+ int pli;
+ int y;
+ int x;
+ /*Skip past the luma data.*/
+ _dst += _y4m->pic_w * _y4m->pic_h;
+ /*Compute the size of each chroma plane.*/
+ c_w = (_y4m->pic_w + _y4m->src_c_dec_h - 1) / _y4m->src_c_dec_h;
+ c_h = _y4m->pic_h;
+ dst_c_w = (_y4m->pic_w + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h;
+ dst_c_h = (_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v;
+ c_sz = c_w * c_h;
+ dst_c_sz = dst_c_w * dst_c_h;
+ tmp_sz = dst_c_w * c_h;
+ tmp = _aux + 2 * c_sz;
+ for (pli = 1; pli < 3; pli++) {
+ /*In reality, the horizontal and vertical steps could be pipelined, for
+ less memory consumption and better cache performance, but we do them
+ separately for simplicity.*/
+ /*First do horizontal filtering (convert to 422jpeg)*/
+ for (y = 0; y < c_h; y++) {
+ /*Filters: [1 110 18 -1]/128 and [-3 50 86 -5]/128, both derived from a
+ 4-tap Mitchell window.*/
+ for (x = 0; x < OC_MINI(c_w, 1); x++) {
+ tmp[x << 1] = (unsigned char)OC_CLAMPI(
+ 0,
+ (111 * _aux[0] + 18 * _aux[OC_MINI(1, c_w - 1)] -
+ _aux[OC_MINI(2, c_w - 1)] + 64) >>
+ 7,
+ 255);
+ tmp[x << 1 | 1] = (unsigned char)OC_CLAMPI(
+ 0,
+ (47 * _aux[0] + 86 * _aux[OC_MINI(1, c_w - 1)] -
+ 5 * _aux[OC_MINI(2, c_w - 1)] + 64) >>
+ 7,
+ 255);
+ }
+ for (; x < c_w - 2; x++) {
+ tmp[x << 1] =
+ (unsigned char)OC_CLAMPI(0,
+ (_aux[x - 1] + 110 * _aux[x] +
+ 18 * _aux[x + 1] - _aux[x + 2] + 64) >>
+ 7,
+ 255);
+ tmp[x << 1 | 1] = (unsigned char)OC_CLAMPI(
+ 0,
+ (-3 * _aux[x - 1] + 50 * _aux[x] + 86 * _aux[x + 1] -
+ 5 * _aux[x + 2] + 64) >>
+ 7,
+ 255);
+ }
+ for (; x < c_w; x++) {
+ tmp[x << 1] = (unsigned char)OC_CLAMPI(
+ 0,
+ (_aux[x - 1] + 110 * _aux[x] + 18 * _aux[OC_MINI(x + 1, c_w - 1)] -
+ _aux[c_w - 1] + 64) >>
+ 7,
+ 255);
+ if ((x << 1 | 1) < dst_c_w) {
+ tmp[x << 1 | 1] = (unsigned char)OC_CLAMPI(
+ 0,
+ (-3 * _aux[x - 1] + 50 * _aux[x] +
+ 86 * _aux[OC_MINI(x + 1, c_w - 1)] - 5 * _aux[c_w - 1] + 64) >>
+ 7,
+ 255);
+ }
+ }
+ tmp += dst_c_w;
+ _aux += c_w;
+ }
+ tmp -= tmp_sz;
+ /*Now do the vertical filtering.*/
+ y4m_422jpeg_420jpeg_helper(_dst, tmp, dst_c_w, c_h);
+ _dst += dst_c_sz;
+ }
+}
+
+/*Convert 444 to 420jpeg.*/
+static void y4m_convert_444_420jpeg(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ unsigned char *tmp;
+ int c_w;
+ int c_h;
+ int c_sz;
+ int dst_c_w;
+ int dst_c_h;
+ int dst_c_sz;
+ int tmp_sz;
+ int pli;
+ int y;
+ int x;
+ /*Skip past the luma data.*/
+ _dst += _y4m->pic_w * _y4m->pic_h;
+ /*Compute the size of each chroma plane.*/
+ c_w = (_y4m->pic_w + _y4m->src_c_dec_h - 1) / _y4m->src_c_dec_h;
+ c_h = _y4m->pic_h;
+ dst_c_w = (_y4m->pic_w + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h;
+ dst_c_h = (_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v;
+ c_sz = c_w * c_h;
+ dst_c_sz = dst_c_w * dst_c_h;
+ tmp_sz = dst_c_w * c_h;
+ tmp = _aux + 2 * c_sz;
+ for (pli = 1; pli < 3; pli++) {
+ /*Filter: [3 -17 78 78 -17 3]/128, derived from a 6-tap Lanczos window.*/
+ for (y = 0; y < c_h; y++) {
+ for (x = 0; x < OC_MINI(c_w, 2); x += 2) {
+ tmp[x >> 1] = OC_CLAMPI(0,
+ (64 * _aux[0] + 78 * _aux[OC_MINI(1, c_w - 1)] -
+ 17 * _aux[OC_MINI(2, c_w - 1)] +
+ 3 * _aux[OC_MINI(3, c_w - 1)] + 64) >>
+ 7,
+ 255);
+ }
+ for (; x < c_w - 3; x += 2) {
+ tmp[x >> 1] = OC_CLAMPI(0,
+ (3 * (_aux[x - 2] + _aux[x + 3]) -
+ 17 * (_aux[x - 1] + _aux[x + 2]) +
+ 78 * (_aux[x] + _aux[x + 1]) + 64) >>
+ 7,
+ 255);
+ }
+ for (; x < c_w; x += 2) {
+ tmp[x >> 1] =
+ OC_CLAMPI(0,
+ (3 * (_aux[x - 2] + _aux[c_w - 1]) -
+ 17 * (_aux[x - 1] + _aux[OC_MINI(x + 2, c_w - 1)]) +
+ 78 * (_aux[x] + _aux[OC_MINI(x + 1, c_w - 1)]) + 64) >>
+ 7,
+ 255);
+ }
+ tmp += dst_c_w;
+ _aux += c_w;
+ }
+ tmp -= tmp_sz;
+ /*Now do the vertical filtering.*/
+ y4m_422jpeg_420jpeg_helper(_dst, tmp, dst_c_w, c_h);
+ _dst += dst_c_sz;
+ }
+}
+
+/*The image is padded with empty chroma components at 4:2:0.*/
+static void y4m_convert_mono_420jpeg(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ int c_sz;
+ (void)_aux;
+ _dst += _y4m->pic_w * _y4m->pic_h;
+ c_sz = ((_y4m->pic_w + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h) *
+ ((_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v);
+ memset(_dst, 128, c_sz * 2);
+}
+
+/*No conversion function needed.*/
+static void y4m_convert_null(y4m_input *_y4m, unsigned char *_dst,
+ unsigned char *_aux) {
+ (void)_y4m;
+ (void)_dst;
+ (void)_aux;
+}
+
+int y4m_input_open(y4m_input *_y4m, FILE *_fin, char *_skip, int _nskip,
+ int only_420) {
+ char buffer[80] = { 0 };
+ int ret;
+ int i;
+ /*Read until newline, or 80 cols, whichever happens first.*/
+ for (i = 0; i < 79; i++) {
+ if (_nskip > 0) {
+ buffer[i] = *_skip++;
+ _nskip--;
+ } else {
+ if (!file_read(buffer + i, 1, _fin)) return -1;
+ }
+ if (buffer[i] == '\n') break;
+ }
+ /*We skipped too much header data.*/
+ if (_nskip > 0) return -1;
+ if (i == 79) {
+ fprintf(stderr, "Error parsing header; not a YUV2MPEG2 file?\n");
+ return -1;
+ }
+ buffer[i] = '\0';
+ if (memcmp(buffer, "YUV4MPEG", 8)) {
+ fprintf(stderr, "Incomplete magic for YUV4MPEG file.\n");
+ return -1;
+ }
+ if (buffer[8] != '2') {
+ fprintf(stderr, "Incorrect YUV input file version; YUV4MPEG2 required.\n");
+ }
+ ret = y4m_parse_tags(_y4m, buffer + 5);
+ if (ret < 0) {
+ fprintf(stderr, "Error parsing YUV4MPEG2 header.\n");
+ return ret;
+ }
+ if (_y4m->interlace == '?') {
+ fprintf(stderr,
+ "Warning: Input video interlacing format unknown; "
+ "assuming progressive scan.\n");
+ } else if (_y4m->interlace != 'p') {
+ fprintf(stderr,
+ "Input video is interlaced; "
+ "Only progressive scan handled.\n");
+ return -1;
+ }
+ _y4m->aom_fmt = AOM_IMG_FMT_I420;
+ _y4m->bps = 12;
+ _y4m->bit_depth = 8;
+ if (strcmp(_y4m->chroma_type, "420") == 0 ||
+ strcmp(_y4m->chroma_type, "420jpeg") == 0) {
+ _y4m->src_c_dec_h = _y4m->dst_c_dec_h = _y4m->src_c_dec_v =
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz =
+ _y4m->pic_w * _y4m->pic_h +
+ 2 * ((_y4m->pic_w + 1) / 2) * ((_y4m->pic_h + 1) / 2);
+ /* Natively supported: no conversion required. */
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ } else if (strcmp(_y4m->chroma_type, "420p10") == 0) {
+ _y4m->src_c_dec_h = 2;
+ _y4m->dst_c_dec_h = 2;
+ _y4m->src_c_dec_v = 2;
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz =
+ 2 * (_y4m->pic_w * _y4m->pic_h +
+ 2 * ((_y4m->pic_w + 1) / 2) * ((_y4m->pic_h + 1) / 2));
+ /* Natively supported: no conversion required. */
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ _y4m->bit_depth = 10;
+ _y4m->bps = 15;
+ _y4m->aom_fmt = AOM_IMG_FMT_I42016;
+ if (only_420) {
+ fprintf(stderr, "Unsupported conversion from 420p10 to 420jpeg\n");
+ return -1;
+ }
+ } else if (strcmp(_y4m->chroma_type, "420p12") == 0) {
+ _y4m->src_c_dec_h = 2;
+ _y4m->dst_c_dec_h = 2;
+ _y4m->src_c_dec_v = 2;
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz =
+ 2 * (_y4m->pic_w * _y4m->pic_h +
+ 2 * ((_y4m->pic_w + 1) / 2) * ((_y4m->pic_h + 1) / 2));
+ /* Natively supported: no conversion required. */
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ _y4m->bit_depth = 12;
+ _y4m->bps = 18;
+ _y4m->aom_fmt = AOM_IMG_FMT_I42016;
+ if (only_420) {
+ fprintf(stderr, "Unsupported conversion from 420p12 to 420jpeg\n");
+ return -1;
+ }
+ } else if (strcmp(_y4m->chroma_type, "420mpeg2") == 0) {
+ _y4m->src_c_dec_h = _y4m->dst_c_dec_h = _y4m->src_c_dec_v =
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*Chroma filter required: read into the aux buf first.*/
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz =
+ 2 * ((_y4m->pic_w + 1) / 2) * ((_y4m->pic_h + 1) / 2);
+ _y4m->convert = y4m_convert_42xmpeg2_42xjpeg;
+ } else if (strcmp(_y4m->chroma_type, "420paldv") == 0) {
+ _y4m->src_c_dec_h = _y4m->dst_c_dec_h = _y4m->src_c_dec_v =
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*Chroma filter required: read into the aux buf first.
+ We need to make two filter passes, so we need some extra space in the
+ aux buffer.*/
+ _y4m->aux_buf_sz = 3 * ((_y4m->pic_w + 1) / 2) * ((_y4m->pic_h + 1) / 2);
+ _y4m->aux_buf_read_sz =
+ 2 * ((_y4m->pic_w + 1) / 2) * ((_y4m->pic_h + 1) / 2);
+ _y4m->convert = y4m_convert_42xpaldv_42xjpeg;
+ } else if (strcmp(_y4m->chroma_type, "422jpeg") == 0) {
+ _y4m->src_c_dec_h = _y4m->dst_c_dec_h = 2;
+ _y4m->src_c_dec_v = 1;
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*Chroma filter required: read into the aux buf first.*/
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz =
+ 2 * ((_y4m->pic_w + 1) / 2) * _y4m->pic_h;
+ _y4m->convert = y4m_convert_422jpeg_420jpeg;
+ } else if (strcmp(_y4m->chroma_type, "422") == 0) {
+ _y4m->src_c_dec_h = 2;
+ _y4m->src_c_dec_v = 1;
+ if (only_420) {
+ _y4m->dst_c_dec_h = 2;
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*Chroma filter required: read into the aux buf first.
+ We need to make two filter passes, so we need some extra space in the
+ aux buffer.*/
+ _y4m->aux_buf_read_sz = 2 * ((_y4m->pic_w + 1) / 2) * _y4m->pic_h;
+ _y4m->aux_buf_sz =
+ _y4m->aux_buf_read_sz + ((_y4m->pic_w + 1) / 2) * _y4m->pic_h;
+ _y4m->convert = y4m_convert_422_420jpeg;
+ } else {
+ _y4m->aom_fmt = AOM_IMG_FMT_I422;
+ _y4m->bps = 16;
+ _y4m->dst_c_dec_h = _y4m->src_c_dec_h;
+ _y4m->dst_c_dec_v = _y4m->src_c_dec_v;
+ _y4m->dst_buf_read_sz =
+ _y4m->pic_w * _y4m->pic_h + 2 * ((_y4m->pic_w + 1) / 2) * _y4m->pic_h;
+ /*Natively supported: no conversion required.*/
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ }
+ } else if (strcmp(_y4m->chroma_type, "422p10") == 0) {
+ _y4m->src_c_dec_h = 2;
+ _y4m->src_c_dec_v = 1;
+ _y4m->aom_fmt = AOM_IMG_FMT_I42216;
+ _y4m->bps = 20;
+ _y4m->bit_depth = 10;
+ _y4m->dst_c_dec_h = _y4m->src_c_dec_h;
+ _y4m->dst_c_dec_v = _y4m->src_c_dec_v;
+ _y4m->dst_buf_read_sz = 2 * (_y4m->pic_w * _y4m->pic_h +
+ 2 * ((_y4m->pic_w + 1) / 2) * _y4m->pic_h);
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ if (only_420) {
+ fprintf(stderr, "Unsupported conversion from 422p10 to 420jpeg\n");
+ return -1;
+ }
+ } else if (strcmp(_y4m->chroma_type, "422p12") == 0) {
+ _y4m->src_c_dec_h = 2;
+ _y4m->src_c_dec_v = 1;
+ _y4m->aom_fmt = AOM_IMG_FMT_I42216;
+ _y4m->bps = 24;
+ _y4m->bit_depth = 12;
+ _y4m->dst_c_dec_h = _y4m->src_c_dec_h;
+ _y4m->dst_c_dec_v = _y4m->src_c_dec_v;
+ _y4m->dst_buf_read_sz = 2 * (_y4m->pic_w * _y4m->pic_h +
+ 2 * ((_y4m->pic_w + 1) / 2) * _y4m->pic_h);
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ if (only_420) {
+ fprintf(stderr, "Unsupported conversion from 422p12 to 420jpeg\n");
+ return -1;
+ }
+ } else if (strcmp(_y4m->chroma_type, "411") == 0) {
+ _y4m->src_c_dec_h = 4;
+ _y4m->dst_c_dec_h = 2;
+ _y4m->src_c_dec_v = 1;
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*Chroma filter required: read into the aux buf first.
+ We need to make two filter passes, so we need some extra space in the
+ aux buffer.*/
+ _y4m->aux_buf_read_sz = 2 * ((_y4m->pic_w + 3) / 4) * _y4m->pic_h;
+ _y4m->aux_buf_sz =
+ _y4m->aux_buf_read_sz + ((_y4m->pic_w + 1) / 2) * _y4m->pic_h;
+ _y4m->convert = y4m_convert_411_420jpeg;
+ } else if (strcmp(_y4m->chroma_type, "444") == 0) {
+ _y4m->src_c_dec_h = 1;
+ _y4m->src_c_dec_v = 1;
+ if (only_420) {
+ _y4m->dst_c_dec_h = 2;
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*Chroma filter required: read into the aux buf first.
+ We need to make two filter passes, so we need some extra space in the
+ aux buffer.*/
+ _y4m->aux_buf_read_sz = 2 * _y4m->pic_w * _y4m->pic_h;
+ _y4m->aux_buf_sz =
+ _y4m->aux_buf_read_sz + ((_y4m->pic_w + 1) / 2) * _y4m->pic_h;
+ _y4m->convert = y4m_convert_444_420jpeg;
+ } else {
+ _y4m->aom_fmt = AOM_IMG_FMT_I444;
+ _y4m->bps = 24;
+ _y4m->dst_c_dec_h = _y4m->src_c_dec_h;
+ _y4m->dst_c_dec_v = _y4m->src_c_dec_v;
+ _y4m->dst_buf_read_sz = 3 * _y4m->pic_w * _y4m->pic_h;
+ /*Natively supported: no conversion required.*/
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ }
+ } else if (strcmp(_y4m->chroma_type, "444p10") == 0) {
+ _y4m->src_c_dec_h = 1;
+ _y4m->src_c_dec_v = 1;
+ _y4m->aom_fmt = AOM_IMG_FMT_I44416;
+ _y4m->bps = 30;
+ _y4m->bit_depth = 10;
+ _y4m->dst_c_dec_h = _y4m->src_c_dec_h;
+ _y4m->dst_c_dec_v = _y4m->src_c_dec_v;
+ _y4m->dst_buf_read_sz = 2 * 3 * _y4m->pic_w * _y4m->pic_h;
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ if (only_420) {
+ fprintf(stderr, "Unsupported conversion from 444p10 to 420jpeg\n");
+ return -1;
+ }
+ } else if (strcmp(_y4m->chroma_type, "444p12") == 0) {
+ _y4m->src_c_dec_h = 1;
+ _y4m->src_c_dec_v = 1;
+ _y4m->aom_fmt = AOM_IMG_FMT_I44416;
+ _y4m->bps = 36;
+ _y4m->bit_depth = 12;
+ _y4m->dst_c_dec_h = _y4m->src_c_dec_h;
+ _y4m->dst_c_dec_v = _y4m->src_c_dec_v;
+ _y4m->dst_buf_read_sz = 2 * 3 * _y4m->pic_w * _y4m->pic_h;
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ if (only_420) {
+ fprintf(stderr, "Unsupported conversion from 444p12 to 420jpeg\n");
+ return -1;
+ }
+ } else if (strcmp(_y4m->chroma_type, "444alpha") == 0) {
+ _y4m->src_c_dec_h = 1;
+ _y4m->src_c_dec_v = 1;
+ if (only_420) {
+ _y4m->dst_c_dec_h = 2;
+ _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*Chroma filter required: read into the aux buf first.
+ We need to make two filter passes, so we need some extra space in the
+ aux buffer.
+ The extra plane also gets read into the aux buf.
+ It will be discarded.*/
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 3 * _y4m->pic_w * _y4m->pic_h;
+ _y4m->convert = y4m_convert_444_420jpeg;
+ } else {
+ _y4m->aom_fmt = AOM_IMG_FMT_444A;
+ _y4m->bps = 32;
+ _y4m->dst_c_dec_h = _y4m->src_c_dec_h;
+ _y4m->dst_c_dec_v = _y4m->src_c_dec_v;
+ _y4m->dst_buf_read_sz = 4 * _y4m->pic_w * _y4m->pic_h;
+ /*Natively supported: no conversion required.*/
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_null;
+ }
+ } else if (strcmp(_y4m->chroma_type, "mono") == 0) {
+ _y4m->src_c_dec_h = _y4m->src_c_dec_v = 0;
+ _y4m->dst_c_dec_h = _y4m->dst_c_dec_v = 2;
+ _y4m->dst_buf_read_sz = _y4m->pic_w * _y4m->pic_h;
+ /*No extra space required, but we need to clear the chroma planes.*/
+ _y4m->aux_buf_sz = _y4m->aux_buf_read_sz = 0;
+ _y4m->convert = y4m_convert_mono_420jpeg;
+ } else {
+ fprintf(stderr, "Unknown chroma sampling type: %s\n", _y4m->chroma_type);
+ return -1;
+ }
+ /*The size of the final frame buffers is always computed from the
+ destination chroma decimation type.*/
+ _y4m->dst_buf_sz =
+ _y4m->pic_w * _y4m->pic_h +
+ 2 * ((_y4m->pic_w + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h) *
+ ((_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v);
+ if (_y4m->bit_depth == 8)
+ _y4m->dst_buf = (unsigned char *)malloc(_y4m->dst_buf_sz);
+ else
+ _y4m->dst_buf = (unsigned char *)malloc(2 * _y4m->dst_buf_sz);
+
+ if (_y4m->aux_buf_sz > 0)
+ _y4m->aux_buf = (unsigned char *)malloc(_y4m->aux_buf_sz);
+ return 0;
+}
+
+void y4m_input_close(y4m_input *_y4m) {
+ free(_y4m->dst_buf);
+ free(_y4m->aux_buf);
+}
+
+int y4m_input_fetch_frame(y4m_input *_y4m, FILE *_fin, aom_image_t *_img) {
+ char frame[6];
+ int pic_sz;
+ int c_w;
+ int c_h;
+ int c_sz;
+ int bytes_per_sample = _y4m->bit_depth > 8 ? 2 : 1;
+ /*Read and skip the frame header.*/
+ if (!file_read(frame, 6, _fin)) return 0;
+ if (memcmp(frame, "FRAME", 5)) {
+ fprintf(stderr, "Loss of framing in Y4M input data\n");
+ return -1;
+ }
+ if (frame[5] != '\n') {
+ char c;
+ int j;
+ for (j = 0; j < 79 && file_read(&c, 1, _fin) && c != '\n'; j++) {
+ }
+ if (j == 79) {
+ fprintf(stderr, "Error parsing Y4M frame header\n");
+ return -1;
+ }
+ }
+ /*Read the frame data that needs no conversion.*/
+ if (!file_read(_y4m->dst_buf, _y4m->dst_buf_read_sz, _fin)) {
+ fprintf(stderr, "Error reading Y4M frame data.\n");
+ return -1;
+ }
+ /*Read the frame data that does need conversion.*/
+ if (!file_read(_y4m->aux_buf, _y4m->aux_buf_read_sz, _fin)) {
+ fprintf(stderr, "Error reading Y4M frame data.\n");
+ return -1;
+ }
+ /*Now convert the just read frame.*/
+ (*_y4m->convert)(_y4m, _y4m->dst_buf, _y4m->aux_buf);
+ /*Fill in the frame buffer pointers.
+ We don't use aom_img_wrap() because it forces padding for odd picture
+ sizes, which would require a separate fread call for every row.*/
+ memset(_img, 0, sizeof(*_img));
+ /*Y4M has the planes in Y'CbCr order, which libaom calls Y, U, and V.*/
+ _img->fmt = _y4m->aom_fmt;
+ _img->w = _img->d_w = _y4m->pic_w;
+ _img->h = _img->d_h = _y4m->pic_h;
+ _img->x_chroma_shift = _y4m->dst_c_dec_h >> 1;
+ _img->y_chroma_shift = _y4m->dst_c_dec_v >> 1;
+ _img->bps = _y4m->bps;
+
+ /*Set up the buffer pointers.*/
+ pic_sz = _y4m->pic_w * _y4m->pic_h * bytes_per_sample;
+ c_w = (_y4m->pic_w + _y4m->dst_c_dec_h - 1) / _y4m->dst_c_dec_h;
+ c_w *= bytes_per_sample;
+ c_h = (_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v;
+ c_sz = c_w * c_h;
+ _img->stride[AOM_PLANE_Y] = _img->stride[AOM_PLANE_ALPHA] =
+ _y4m->pic_w * bytes_per_sample;
+ _img->stride[AOM_PLANE_U] = _img->stride[AOM_PLANE_V] = c_w;
+ _img->planes[AOM_PLANE_Y] = _y4m->dst_buf;
+ _img->planes[AOM_PLANE_U] = _y4m->dst_buf + pic_sz;
+ _img->planes[AOM_PLANE_V] = _y4m->dst_buf + pic_sz + c_sz;
+ _img->planes[AOM_PLANE_ALPHA] = _y4m->dst_buf + pic_sz + 2 * c_sz;
+ return 1;
+}