}
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++;
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;
}
+// Copy a single tag into the buffer, along with a null character.
+// Returns 0 if any file IO errors occur.
+static int copy_tag(char *buf, size_t buf_len, char *end_tag, FILE *file) {
+ size_t i;
+ assert(buf_len >= 1);
+ // Skip leading space characters.
+ do {
+ if (!file_read(buf, 1, file)) {
+ return 0;
+ }
+ } while (buf[0] == ' ');
+
+ // If we hit the newline, treat this as the "empty" tag.
+ if (buf[0] == '\n') {
+ buf[0] = '\0';
+ *end_tag = '\n';
+ return 1;
+ }
+
+ // Copy over characters until a space is hit, or the buffer is exhausted.
+ for (i = 1; i < buf_len; ++i) {
+ if (!file_read(buf + i, 1, file)) {
+ return 0;
+ }
+ if (buf[i] == ' ' || buf[i] == '\n') {
+ break;
+ }
+ }
+ if (i == buf_len) {
+ fprintf(stderr, "Error: Y4M header tags must be less than %lu characters\n",
+ (unsigned long)i);
+ return 0;
+ }
+ *end_tag = buf[i];
+ buf[i] = '\0';
+ return 1;
+}
+
+/* Returns 1 if tags were parsed successfully, 0 otherwise. */
+static int parse_tags(y4m_input *y4m_ctx, FILE *file) {
+ char tag[256];
+ char end; /* Character denoting the end of the tag, ' ' or '\n'. */
+ /* Set Y4M tags to defaults, updating them as processing occurs. Mandatory
+ fields are marked with -1 and will be checked after the tags are parsed. */
+ y4m_ctx->pic_w = -1;
+ y4m_ctx->pic_h = -1;
+ y4m_ctx->fps_n = -1; /* Also serves as marker for fps_d */
+ y4m_ctx->par_n = 0;
+ y4m_ctx->par_d = 0;
+ y4m_ctx->interlace = '?';
+ snprintf(y4m_ctx->chroma_type, sizeof(y4m_ctx->chroma_type), "420");
+
+ /* Find one tag at a time. */
+ do {
+ if (!copy_tag(tag, sizeof(tag), &end, file)) {
+ return 0;
+ }
+ /* y4m_parse_tags returns 0 on success. */
+ if (y4m_parse_tags(y4m_ctx, tag)) {
+ return 0;
+ }
+ } while (end != '\n');
+
+ /* Check the mandatory fields. */
+ if (y4m_ctx->pic_w == -1) {
+ fprintf(stderr, "Width field missing\n");
+ return 0;
+ }
+ if (y4m_ctx->pic_h == -1) {
+ fprintf(stderr, "Height field missing\n");
+ return 0;
+ }
+ if (y4m_ctx->fps_n == -1) {
+ fprintf(stderr, "FPS field missing\n");
+ return 0;
+ }
+ return 1;
+}
+
/*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):
}
}
-/*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.
int num_skip, int only_420) {
// File must start with |TAG|.
char tag_buffer[9]; // 9 == strlen(TAG)
- char buffer[80] = { 0 };
- int ret;
- int i;
// Read as much as possible from |skip_buffer|, which were characters
// that were previously read from the file to do input-type detection.
assert(num_skip >= 0 && num_skip <= 8);
return -1;
}
// Next character must be a space.
- if (!file_read(buffer, 1, file) || buffer[0] != ' ') {
+ if (!file_read(tag_buffer, 1, file) || tag_buffer[0] != ' ') {
fprintf(stderr, "Error parsing header: space must follow %s\n", TAG);
return -1;
}
- /*Read until newline, or 80 cols, whichever happens first.*/
- for (i = 0; i < 79; i++) {
- if (!file_read(buffer + i, 1, file)) return -1;
- if (buffer[i] == '\n') break;
- }
- /*We skipped too much header data.*/
- if (i == 79) {
- fprintf(stderr, "Error parsing header; not a YUV4MPEG2 file?\n");
- return -1;
- }
- buffer[i] = '\0';
- ret = y4m_parse_tags(y4m_ctx, buffer);
- if (ret < 0) {
- fprintf(stderr, "Error parsing YUV4MPEG2 header.\n");
- return ret;
+ if (!parse_tags(y4m_ctx, file)) {
+ fprintf(stderr, "Error parsing %s header.\n", TAG);
}
if (y4m_ctx->interlace == '?') {
fprintf(stderr,
y4m_ctx->aux_buf = NULL;
y4m_ctx->dst_buf = NULL;
if (strcmp(y4m_ctx->chroma_type, "420") == 0 ||
- strcmp(y4m_ctx->chroma_type, "420jpeg") == 0) {
+ strcmp(y4m_ctx->chroma_type, "420jpeg") == 0 ||
+ strcmp(y4m_ctx->chroma_type, "420mpeg2") == 0) {
y4m_ctx->src_c_dec_h = y4m_ctx->dst_c_dec_h = y4m_ctx->src_c_dec_v =
y4m_ctx->dst_c_dec_v = 2;
y4m_ctx->dst_buf_read_sz =
fprintf(stderr, "Unsupported conversion from 420p12 to 420jpeg\n");
return -1;
}
- } else if (strcmp(y4m_ctx->chroma_type, "420mpeg2") == 0) {
- y4m_ctx->src_c_dec_h = y4m_ctx->dst_c_dec_h = y4m_ctx->src_c_dec_v =
- y4m_ctx->dst_c_dec_v = 2;
- y4m_ctx->dst_buf_read_sz = y4m_ctx->pic_w * y4m_ctx->pic_h;
- /*Chroma filter required: read into the aux buf first.*/
- y4m_ctx->aux_buf_sz = y4m_ctx->aux_buf_read_sz =
- 2 * ((y4m_ctx->pic_w + 1) / 2) * ((y4m_ctx->pic_h + 1) / 2);
- y4m_ctx->convert = y4m_convert_42xmpeg2_42xjpeg;
} else if (strcmp(y4m_ctx->chroma_type, "420paldv") == 0) {
y4m_ctx->src_c_dec_h = y4m_ctx->dst_c_dec_h = y4m_ctx->src_c_dec_v =
y4m_ctx->dst_c_dec_v = 2;
y4m_ctx->dst_buf = (unsigned char *)malloc(y4m_ctx->dst_buf_sz);
else
y4m_ctx->dst_buf = (unsigned char *)malloc(2 * y4m_ctx->dst_buf_sz);
+ if (!y4m_ctx->dst_buf) return -1;
- if (y4m_ctx->aux_buf_sz > 0)
+ if (y4m_ctx->aux_buf_sz > 0) {
y4m_ctx->aux_buf = (unsigned char *)malloc(y4m_ctx->aux_buf_sz);
+ if (!y4m_ctx->aux_buf) {
+ free(y4m_ctx->dst_buf);
+ return -1;
+ }
+ }
return 0;
}
projects / platform / upstream / libvpx.git / blobdiff