FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                         No. 06-10546
                Plaintiff-Appellee,
               v.                                   D.C. No.
                                                  CR-05-0025-AWI
RICHARD SALCIDO,
                                                     OPINION
             Defendant-Appellant.
                                            
         Appeal from the United States District Court
            for the Eastern District of California
         Anthony W. Ishii, District Judge, Presiding

                    Argued and Submitted
          August 13, 2007—San Francisco, California

                      Filed October 19, 2007

 Before: Eugene E. Siler, Jr.,* M. Margaret McKeown, and
              Carlos T. Bea, Circuit Judges.

                        Per Curiam Opinion




   *The Honorable Eugene E. Siler, Jr., Senior United States Circuit Judge
for the Sixth Circuit, sitting by designation.

                                 14119
                  UNITED STATES v. SALCIDO            14121


                        COUNSEL

Daniel J. Broderick, Federal Defender, Robert W. Rainwater,
Assistant Federal Defender, Fresno, California, for the
defendant-appellant.

McGregor W. Scott, United States Attorney, Sherrill A. Car-
valho, Assistant United States Attorney, Fresno, California,
for the plaintiff-appellee.
14122              UNITED STATES v. SALCIDO
                          OPINION

PER CURIAM:

   Richard Salcido appeals his conviction and sentence for
receipt or distribution of material involving the sexual exploi-
tation of minors, in violation of 18 U.S.C. § 2252(a)(2), and
possession of material involving the sexual exploitation of
minors, in violation of 18 U.S.C. § 2252(a)(4)(B). He argues:
(1) the district court erred in admitting movie and image files
into evidence because the government did not establish that
the movie and image files actually depicted a minor; (2) with-
out this evidence, there is insufficient evidence that he pos-
sessed authentic material depicting the sexual exploitation of
an actual minor; (3) admission of sexually explicit chat logs
was irrelevant and unduly prejudicial since he conceded the
issue of knowledge; (4) the district court lacked a sufficient
factual basis to enhance his sentence pursuant to USSG
§ 2G2.2(b)(7)(D); and (5) the district court erred by failing to
hold an evidentiary hearing to determine the number of
images he possessed. We affirm.

                    I.   BACKGROUND

   In February 2005, Detective Ken Hedrick of the Stanislaus
County Sheriff’s Department conducted an investigation into
peer-to-peer file sharing of child pornography on the Internet.
He utilized a program to locate files containing child pornog-
raphy by searching for the term “babyj” and compared his
search results with a list of known child pornography files. He
then obtained a list of IP addresses that had those files avail-
able for downloading. Upon finding a computer in California
that had child pornography files available for sharing, Hedrick
referred the information to the Bureau of Immigration and
Customs Enforcement for additional investigation. The
Bureau sent a summons to the Internet service provider to
obtain subscriber information for the California computer.
                   UNITED STATES v. SALCIDO               14123
   Using the subscriber information, Special Agent Mike
Prado obtained a search warrant for the address of the defen-
dant, Salcido. When the search warrant was executed in Feb-
ruary 2005, two computers and a CD-ROM were seized from
the residence. At the time of the search, Salcido initially
stated that he had not purposely obtained child pornography,
but he would often download it inadvertently while searching
for adult pornography. Later, he admitted to purposely obtain-
ing and viewing child pornography over the Internet.

   Detective Kevin Wiens conducted a forensic examination
of the computer hard drives and CD-ROM found at Salcido’s
residence. During his examination, Wiens located movie files
and still images of child pornography as well as sexually
explicit chat logs. Agent Prado had a second interview with
Salcido in July 2005. Salcido again initially claimed that any
child pornography on his computer was downloaded inadver-
tently, but he later admitted to using the search terms “kiddie”
and “pedo” out of curiosity while using peer-to-peer software.
As Prado later testified, these are terms “commonly used in
the verbiage . . . of people involved in child pornography.”
Salcido also told Prado that he felt an adrenaline rush when
viewing child pornography because he knew it was illegal and
that he was excited by children ages 10 to 13 engaged in sexu-
ally explicit activity. He further admitted to having sexually
explicit conversations about children via Yahoo! Instant Mes-
senger and to obtaining and distributing child pornography
while using the instant messaging service. At this second
interview, Salcido also signed a written statement acknowl-
edging that what he had done was “illegal and immoral.”

   During the trial, the government introduced into evidence
five videos and six still images that were found on Salcido’s
hard drives and CD-ROM. Detective James Smith of the Con-
necticut State Police testified that he recognized one of the
videos based on a previous investigation he conducted in
Connecticut. He further testified that he identified one of the
14124                UNITED STATES v. SALCIDO
girls who appeared in the video and that he interviewed her
several times, for approximately four hours.

               II.   STANDARD OF REVIEW

   A district court’s decision to admit evidence is reviewed for
an abuse of discretion. United States v. Sua, 

,
1152 (9th Cir. 2002); United States v. Tank, 

,
630 (9th Cir. 2000). Claims of insufficient evidence are
reviewed de novo. United States v. Odom, 

,
1034 (9th Cir. 2003). There is sufficient evidence to support
a conviction if, viewing the evidence in the light most favor-
able to the government, “any rational trier of fact could have
found the essential elements of the crime beyond a reasonable
doubt.” 

court’s factual findings during the sen-
tencing phase are reviewed for clear error. United States v.
Bynum, 

, 993 (9th Cir. 2003). Under the clear
error standard, we will “defer to the district court unless we
are ‘left with the definite and firm conviction that a mistake
has been committed.’ ” United States v. MacDonald, 

, 1082-83 (9th Cir. 2003) (quoting United States v.
Crook, 

, 1427 (9th Cir. 1993)).

                      III.   DISCUSSION

   Salcido’s first claim is that the district court erred by admit-
ting the video and image files into evidence because the gov-
ernment did not establish their authenticity. The requirement
of authentication prior to admissibility “is satisfied by evi-
dence sufficient to support a finding that the matter in ques-
tion is what its proponent claims.” Fed. R. Evid. 901(a). In
this case, the government properly authenticated the videos
and images under Rule 901 by presenting detailed evidence as
to the chain of custody, specifically how the images were
retrieved from the defendant’s computers. Salcido does not
contest that the files were obtained from his computers nor
that they appear to be child pornography; rather, he asserts
                       UNITED STATES v. SALCIDO                      14125
that the government failed to present evidence that the files
depicted an actual minor.

   [1] While Salcido frames this as an issue of authenticity,
this argument is more properly considered a challenge to the
sufficiency of the evidence. See United States v. Nolan, 

, 1016-17 (1st Cir. 1987) (“Whether the pictures
were the kind of visual depictions the law forbids, i.e., ones
involving the ‘use’ of actual minors engaging in sexually
explicit conduct, 18 U.S.C. § 2252(a)(2)(A), goes more prop-
erly to whether the government presented sufficient evidence
to prove all the elements of its case than to ‘authentica-
tion.’ ”), abrogated on other grounds by United States v. Hil-
ton (Hilton I), 

(1st Cir. 2004), withdrawn, United
States v. Hilton (Hilton II), 

(1st Cir. 2004).1 We
agree with the First Circuit’s characterization of this argu-
ment. Our interpretation is also in line with a recent Sixth Cir-
cuit ruling that the government is generally permitted to
present child pornographic images and must subsequently
present proof that the images depict actual children. United
States v. Sheldon, 223 F. App’x 478, 483 (6th Cir. 2007) (not-
ing that the government is not required to “pre-screen, or pre-
authenticate, child pornographic images to make sure that
they are indeed real”).

   [2] The principal issue in the case is raised by Salcido’s
second argument—that the government’s evidence is insuffi-
cient to prove the videos and images depicted an actual minor.
In Ashcroft v. Free Speech Coalition, the Supreme Court held
that possession of “virtual” child pornography cannot consti-
tute a criminal offense. 

, 239-40, 258 (2002). As
a result, the government has the burden of proving beyond a
  1
    The First Circuit recently clarified the status of Nolan by expressly
stating that Nolan has not been overruled and by declining to abandon the
rule of Nolan that expert testimony is not per se required to prove that por-
nographic images depict real children. United States v. Rodriguez-
Pacheco, 

, 439, 442 (1st Cir. 2007).
14126                  UNITED STATES v. SALCIDO
reasonable doubt that the images were of actual children, not
computer-generated images. United States v. Rearden, 

, 613 (9th Cir. 2003). Salcido argues that the only
evidence from which the jury could have concluded the
images depicted genuine child pornography were the images
themselves, and he asserts that the government was required
to present more evidence, perhaps including expert testimony,
on this issue.

   [3] As the Sixth Circuit noted, “at this time, it appears that
no circuit requires that expert evidence be introduced to prove
the reality of children portrayed in pornographic images.”
United States v. Farrelly, 

, 654 n.4 (6th Cir.
2004), abrogated on other grounds by United States v. Wil-
liams, 

, 678 n.1 (6th Cir. 2005); see also United
States v. Rodriguez-Pacheco, 

, 437 (1st Cir.
2007). We agree with every other circuit that has ruled on the
issue that expert testimony is not required for the government
to establish that the images depicted an actual minor.2

   With respect to the quantum of evidence necessary to sup-
port a conviction, there seems to be general agreement among
the circuits that pornographic images themselves are suffi-
cient to prove the depiction of actual minors. See, e.g., United
States v. Irving, 

, 121-22 (2d Cir. 2006) (reject-
ing claim that the government must present extrinsic evidence
to prove the reality of children in video images); United States
v. Slanina, 

, 357 (5th Cir. 2004) (per curiam)
(holding extrinsic evidence was not required to prove reality
of children in images); United States v. Kimler, 

, 1142 (10th Cir. 2003) (“Juries are still capable of distin-
  2
   For a brief period, the First Circuit had a rule that obligated the govern-
ment to produce expert testimony to meet its burden of proving images
depicted real minors; however, that opinion was subsequently withdrawn.
See 

(discussing United States v.
Hilton, 

(1st Cir. 2004), and its withdrawal by United States
v. Hilton, 

(1st Cir. 2004)).
                    UNITED STATES v. SALCIDO               14127
guishing between real and virtual images . . . .”); United
States v. Deaton, 

, 455 (8th Cir. 2003) (uphold-
ing jury determination that images depicted real children even
where no additional evidence was presented on the issue). In
cases regarding the effect of erroneous jury instructions, some
appellate courts have examined the images themselves and
determined that actual children were depicted. See Becht v.
United States, 

, 549 (8th Cir. 2005) (concluding
upon examination of images “that ‘no rational juror, if prop-
erly instructed’ could find that the depictions were not of
actual minors”); United States v. Hall, 

, 1260
(11th Cir. 2002).

   On the other hand, the First Circuit had a short-lived opin-
ion that expressly required the government to “introduce rele-
vant evidence in addition to the images to prove the children
are real.” Hilton 

. However, this opinion was
withdrawn, Hilton II, 

, and the First Circuit has
left the issue open in subsequent decisions. In support of the
argument that extrinsic evidence is required to prove the real-
ity of the children depicted, Salcido cites specifically to the
district court opinion in United States v. Frabizio, 445 F.
Supp. 2d 152 (D. Mass. 2006). The court in Frabizio ruled
that “neither an expert witness nor a lay jury, using only
visual means, can determine whether the images in this case
are real or virtual to the level of certainty required in a crimi-
nal prosecution.” 

It is important to note, however,
that Frabizio involved only still photographs, whereas video
files comprise the bulk of the images obtained from Salcido’s
computers. Additionally, the court in Frabizio specifically
noted that its conclusions were limited to the images in the
case before it. 

n.8. As a result, the persuasiveness
of the Frabizio court’s analysis is significantly limited.

  When this court faced a similar claim of insufficient evi-
dence in Rearden, the conviction was sustained on two bases
—Rearden admitted knowledge that one of the images he sent
was of a minor, and it was “obvious from the pictures them-
14128               UNITED STATES v. SALCIDO
selves” that they depicted minors. 

.
Likewise, in this case, we need not decide whether the jury
may determine the reality of persons depicted in images based
solely on the images themselves. Here, the government pre-
sented additional evidence from which the jury could con-
clude that the images depicted actual children.

   [4] First, Detective Smith testified that during his investiga-
tion in Connecticut, he identified the victim depicted in one
of the videos found on Salcido’s computer. Smith further tes-
tified that he interviewed the girl on several occasions. Based
on this information, the jury could have concluded that the
girl in the video was an actual person. Further, the jury heard
testimony from Agent Prado that Salcido admitted to viewing
and downloading child pornography on the Internet. During
Prado’s second interview, Salcido also admitted his interest in
child pornography, particularly in children ages 10 to 13, and
stated that he obtained child pornography from individuals he
communicated with via Yahoo! Instant Messenger. These
admissions provide a basis for the jury to conclude that the
defendant knowingly received and possessed child pornogra-
phy. Viewing the evidence in the light most favorable to the
government, we find there is sufficient evidence to sustain the
conviction.

  [5] Salcido next argues that the evidence of sexually
explicit chat logs admitted to show knowledge of possession
and receipt of child pornography was irrelevant and unduly
prejudicial since he conceded the issue of knowledge. How-
ever, the chat logs were relevant to establish that Salcido
knew the images on his computer depicted minors. Fed. R.
Evid. 401. Moreover, the probative value of the chat logs was
not substantially outweighed by the danger of unfair prejudice
because Salcido’s failure to defend on the issue of knowledge
did not relieve the government of its burden to prove this ele-
ment beyond a reasonable doubt. Fed. R. Evid. 403.

  [6] Salcido also claims that the district court erred by
enhancing his sentence pursuant to USSG § 2G2.2(b)(7)(D)
                    UNITED STATES v. SALCIDO                14129
for possessing more than 600 images of child pornography.
His argument is twofold: (1) there was an insufficient basis to
impose the enhancement, and (2) he was entitled to an eviden-
tiary hearing to determine the number of images he possessed.
First, there was a sufficient factual record to impose the
enhancement. Agent Prado stated that six videos and 185 still
images of child pornography were found on Salcido’s hard
drives and CD-ROM. Pursuant to USSG § 2G2.2, Application
Note 4(B)(ii), each video is considered to contain 75 images.
Thus, the number of images possessed at the time of the exe-
cution of the search warrant alone is sufficient to support the
enhancement. The court also had evidence that as many as ten
additional child pornography videos were on Salcido’s com-
puter at the time of Detective Hedrick’s initial peer-to-peer
file sharing investigation. In light of this evidence, the district
court did not commit clear error in finding that Salcido pos-
sessed more than 600 images.

   [7] Further, the district court’s failure to hold an evidentiary
hearing was not error. Rule 32 of the Federal Rules of Crimi-
nal Procedure “does not create a ‘general right to an evidenti-
ary hearing at sentencing.’ ” United States v. Stein, 

, 780 (9th Cir. 1997). The district court complied with
Rule 32 in this case because Salcido was permitted to file
written objections to the presentence report and was given the
opportunity to make additional arguments at the sentencing
hearing. See 

(noting that as long as the district
court permits the defendant to rebut a presentence report’s
recommendation, either orally or through submission of
papers, Rule 32 does not require an evidentiary hearing).
Therefore, the 108-month sentence imposed by the district
court was not unreasonable or erroneous.

  AFFIRMED.